Some may be broken been a while since I checked them all.

Page Rank

Rank Checker ([Only registered and activated users can see links. ]) - Get a overview of your website's ranking
PageRank Lookup ([Only registered and activated users can see links. ]) - check the PageRank for a website
Google PageRank Prediction ([Only registered and activated users can see links. ]) - check predicted PR of a site
Multi-Rank Checker ([Only registered and activated users can see links. ]) - View your Google PageRank and Alexa Ranking in bulk
PageRank Checker ([Only registered and activated users can see links. ]) - View your Google PageRank on differnet Google servers

Links related

Reciprocal Link Check ([Only registered and activated users can see links. ]) - check whether your link partners are linking back to your website
Link Popularity Checker ([Only registered and activated users can see links. ]) - a popularity score given to a website based on inbound links
LinkPrice Lookup ([Only registered and activated users can see links. ]) - check the price of your link
Link Price Calculator ([Only registered and activated users can see links. ]) - another tool for checking the price of links
Link Checker ([Only registered and activated users can see links. ]) - check your links to see if it's still valid or not
Link Popularity ([Only registered and activated users can see links. ]) - checks the total number of web pages which link to a website
Link Price Calculator ([Only registered and activated users can see links. ]) - help to determine the approximate amount you should be paying (or charging) per month for a text link (ad) from each and every page of the specified website
Site Link Analyzer ([Only registered and activated users can see links. ]) - analyze a given web page and return a table of data containing columns of outbound links and their associated anchor text
URL Rewriting ([Only registered and activated users can see links. ]) - convert dynamic URLs into static looking HTML URLs
Link Extractor ([Only registered and activated users can see links. ]) - Extract links from a specific web page
Link Shortener ([Only registered and activated users can see links. ]) - shorten a web address
Backlink Anchor Text Analyzer ([Only registered and activated users can see links. ]) - check link text used by your backlinks to Link to your wesbite

Keyword related

Keyword Verification ([Only registered and activated users can see links. ]) - checks to see if your site is in the top three pages of a search engine result for a specific keyword
Keyword Density Analyser ([Only registered and activated users can see links. ]) - another SEO tools for keywords
Keyword Cloud ([Only registered and activated users can see links. ]) - a visual representation of keywords used on a website
Keyword Density ([Only registered and activated users can see links. ]) - another SEO tool for checking keyword density
Keyword Difficulty Check ([Only registered and activated users can see links. ]) - see how difficult it would be to rank for specific keywords or phrases
Keyword Optimizer ([Only registered and activated users can see links. ]) - optimizer your keywords with this tool
Keyword Suggestion ([Only registered and activated users can see links. ]) - Find related keywords matching your search

Sitemap

XML-Sitemaps ([Only registered and activated users can see links. ]) - Build your Site Map online (XML, ROR, Text, HTML)
Gsitecrawler ([Only registered and activated users can see links. ]) - Google (and Yahoo!) Sitemap Generator for Windows
Validate XML Sitemap ([Only registered and activated users can see links. ]) - Search Engine Optimizion Tool for validating your xml sitemaps

Search Engines

Google Analytics ([Only registered and activated users can see links. ]) - tells you everything about your visitors
Google Banned Checker ([Only registered and activated users can see links. ]) - check whether a site is banned by Google or not
Search Engine Bot Simulator ([Only registered and activated users can see links. ]) - SEO Tool to simulate search engine parsing of webpages and display discovered links.
Indexed pages ([Only registered and activated users can see links. ]) - check the no. of indexed pages for your blog
Spider Simulator ([Only registered and activated users can see links. ]) - simulates a search engine by displaying the contents of a web page
Search Engine Friendly Redirect Checker ([Only registered and activated users can see links. ]) - checks the exact HTTP headers that a web server is sending with an HTTP response.
Search Engine Position ([Only registered and activated users can see links. ]) - Locate your search listings on Google and Yahoo!
Search Listings Preview ([Only registered and activated users can see links. ]) - Preview your website on Google, MSN and Yahoo! Search

HTML related

HTML Encrypt ([Only registered and activated users can see links. ]) - Hide your HTML source code
HTML Optimizer ([Only registered and activated users can see links. ]) - Optimize and clean your HTML source code
HTTP Headers ([Only registered and activated users can see links. ]) - Extract the HTTP Headers of a web page
HTTP Headers Viewer ([Only registered and activated users can see links. ]) - check HTTP headers for any specific URL
Meta-tags Extractor ([Only registered and activated users can see links. ]) - Extract meta-tags information from a web page
Meta-tags Generator ([Only registered and activated users can see links. ]) - Generate and configure your meta-tags
META Analyzer ([Only registered and activated users can see links. ]) - analyze a website's meta tags
Meta Tag Generator ([Only registered and activated users can see links. ]) - help you to generate meta tags
Source Code Viewer ([Only registered and activated users can see links. ]) - View the source code of a page

Domain related

Alexa Traffic Rank ([Only registered and activated users can see links. ]) - View and compare Alexa Ranking graphs
Domain Age Tool ([Only registered and activated users can see links. ]) - find out the age of your competitor's domains
Domain Stats Tool ([Only registered and activated users can see links. ]) - get all kind of statistics of your competitor's domains
Domain Availability ([Only registered and activated users can see links. ]) - Check the availability of domains
Domain Look-up ([Only registered and activated users can see links. ]) - Retrieve a range of information about a domain
Domain Whois ([Only registered and activated users can see links. ]) - Retrieve domain whois information
Instant Domain Checker ([Only registered and activated users can see links. ]) - Check the availability of domains instantly
Ping Test ([Only registered and activated users can see links. ]) - Check the presence of an active connection
Reverse IP/Look-up ([Only registered and activated users can see links. ]) - Resolve a host to an IP address
Server Status ([Only registered and activated users can see links. ]) - Check if your website is online or offline
Website Speed Test ([Only registered and activated users can see links. ]) - Find out how fast your website loads
What Is My IP Address ([Only registered and activated users can see links. ]) - shows your ip address
IP to City ([Only registered and activated users can see links. ]) - determine the Country, City, Latitude and Longitude of an IP Address
Website to Country ([Only registered and activated users can see links. ]) - determine the Country in which the specified website is Hosted

Web stats

Statcounter ([Only registered and activated users can see links. ]) - famous free web tracker
HiStats ([Only registered and activated users can see links. ]) - Free, real time updated web stats service
Addfreestats ([Only registered and activated users can see links. ]) - provide free website statistics

Miscellaneous

FEED Validator ([Only registered and activated users can see links. ]) - for Atom and RSS
W3C Markup Validation Service ([Only registered and activated users can see links. ]) - check for conformance to W3C Recommendations and other standards
Kontera Ads Preview ([Only registered and activated users can see links. ]) - preview Kontera Ads on your website
Online spell checker ([Only registered and activated users can see links. ]) - simple online spell checking tools
Browser Screen Resolution Checker ([Only registered and activated users can see links. ]) - shows what your site looks like with different screen resolutions
Your Browser Details ([Only registered and activated users can see links. ]) - View your IP address and your browser details
Anonymous Emailer ([Only registered and activated users can see links. ]) - Send e-mails to users anonymously
md5 Encrypt ([Only registered and activated users can see links. ]) - Encrypt text to MD5
Online Calculator ([Only registered and activated users can see links. ]) - A simple online calculator

Google

1. Reporting Spam to Google -https://www.google.com/contact/spamreport.html
2. Use Google to search your website - [Only registered and activated users can see links. ]
3. Submit your website to Google - [Only registered and activated users can see links. ]
4. Monitor Keyword Phrases - [Only registered and activated users can see links. ] (This is neat to check out however does not help that much)
5. Googles Guidelines for Websmasters - [Only registered and activated users can see links. ] (A must read new people)
6. Facts for Webmasters - [Only registered and activated users can see links. ]
7. Having Trouble? Contact Google Directly - [Only registered and activated users can see links. ]

Website Design & Tools

1. Free Forms for your website TFMail - [Only registered and activated users can see links. ]
2. Validate Your HTML - [Only registered and activated users can see links. ]
3. HTTP Error Code Meanings - [Only registered and activated users can see links. ] ([Only registered and activated users can see links. ])
4. Keyword Tracking - [Only registered and activated users can see links. ]
5. Link Checker - [Only registered and activated users can see links. ] ([Only registered and activated users can see links. ]) 6. Search Engine Relationship Chart - [Only registered and activated users can see links. ] ([Only registered and activated users can see links. ])
Bruce Clay does an excellent job of keeping this updated.
7. Link Popularity Checker (Uptime Bot) - [Only registered and activated users can see links. ]
8. Character Counting - [Only registered and activated users can see links. ] (This is great when optimizing your title or meta tags)
9. Character Encoding - [Only registered and activated users can see links. ] ([Only registered and activated users can see links. ]) (Ever wonder what those iso-8859-4 or utf-8 were or how to use them?)
10. Converting Hex to Dec or Vias Versa - [Only registered and activated users can see links. ]
11. Ascii-Dec-Hex Conversion Code Chart - [Only registered and activated users can see links. ]
12. Ascii-HTML View Conversion Chart - [Only registered and activated users can see links. ] (This is an excellent resource when placing ascii code on your website. Remember to use the correct character encoding)
13. Ascii Chart in .GIF Format - [Only registered and activated users can see links. ]
14. Customer Focus Tool - [Only registered and activated users can see links. ] (Tells you whether your website is focused on your customers or not)
15. Dead Link Checker - [Only registered and activated users can see links. ] (Doesn't crawl links within Frames or JavaScript)
16. Adsense Simulator - [Only registered and activated users can see links. ] (This will give you an idea of what ads will be displayed on your website before you place them)
17. Google Page Rank Calculator - [Only registered and activated users can see links. ] (This is an advanced tool for finding out what you need to get your PR to the next level.)
18. Page Rank Finder - [Only registered and activated users can see links. ] (This is a great tool to find quality websites with the PR that you are looking for to exchange websites with. This tool only looks at the home page not the link pages. This tool looks at 10 pages or 100 results)
19. Future Google PR - [Only registered and activated users can see links. ] ([Only registered and activated users can see links. ]) - This is an article that tells you what datacenter your Google PR is udpated on first.
20. Keyword Analysis Tool - [Only registered and activated users can see links. ] - This tool is a must. It's quick and easy to use
21. Keyword Density Analyzer - [Only registered and activated users can see links. ]
22. Keyword Difficulty Checker - [Only registered and activated users can see links. ] (You will need a Google API for this one)
23. Free Google API - [Only registered and activated users can see links. ]
24. Rocket Rank - [Only registered and activated users can see links. ] - This will only check the top 20 of the following SE's:
(All The Web DMOZ AltaVista Overture Excite Web Crawler HotBot Lycos What U Seek Yahoo)
Keyword Suggestion Tools:
25. WordTracker & Overture Suggestions [Only registered and activated users can see links. ] - This is the best one of the three
26. Adwords Suggestion - [Only registered and activated users can see links. ]
27. Overture Suggestion - [Only registered and activated users can see links. ]
28. Link Analyzer - [Only registered and activated users can see links. ] Analyze the ratio of internal liinks vs. external links. This is a good tool when determining page rank leakage.
29. Link Appeal - [Only registered and activated users can see links. ] (Want to know whether or not you actually want your link on that page?)
30. Link City - [Only registered and activated users can see links. ] (This place has EVERY tool under the sun for everything you could ever possibly want)
31. Link Reputation - [Only registered and activated users can see links. ] (Reveals baclinks pointing to the target URL along with a link survey for eack backlink.)
32. Google PR Tools - [Only registered and activated users can see links. ] (This guy has tons of fantastic tools. He is not as popular as some of the rest but the tools are great)
33. Protect Your e-mail address - [Only registered and activated users can see links. ] (Obfuscates your e-mail so spambots don't pick it up from the Internet)
34. Digital Points Ad Network - [Only registered and activated users can see links. ] - After using all of the tools and more on this page. This has helped out the rankings faster than anything else.
35. Sandbox Detection Tool - [Only registered and activated users can see links. ] - Is your website being sandboxed?
36. Spider Simulation - [Only registered and activated users can see links. ] - See what the spider sees on your website
37. SEO-Toys - [Only registered and activated users can see links. ] - These are some things that I had in my favorites. Some of them are okay.
38. Multiple SEO Tools - [Only registered and activated users can see links. ] - This website has a variety of misc. tools on it that you can use to better your search engine rankings.
39. Bot Spotter - [Only registered and activated users can see links. ] - This is a phenomenal script that will track what bots hit your website at what times. (Runs on PHP enabled websites)
40. Net Mechanic - [Only registered and activated users can see links. ] - This will break your website down and tell you any errors that you may be unaware of.
41. Statcounter - [Only registered and activated users can see links. ] - This will track your clients throughout the dynamically created pages of your website. This is a free service.
42. Dr. HTML - [Only registered and activated users can see links. ] - This will test your website for any errors that you may be unaware of and tell you how to fix them.
43. Page Rank Calculation - [Only registered and activated users can see links. ]

Newsletters & Articles

1. Site Pro News - [Only registered and activated users can see links. ] ([Only registered and activated users can see links. ])
2. In Stat - [Only registered and activated users can see links. ] (This has some decent insite)
3. Page Rank Explained - [Only registered and activated users can see links. ] ([Only registered and activated users can see links. ])
4. Seach Engine Ratings and Reviews - [Only registered and activated users can see links. ]
5. Database of Robots - [Only registered and activated users can see links. ]
(Ever wondered anything about the spiders that are out there?)

ISAPI Rewrites

1. URL Replacer - (Free) - [Only registered and activated users can see links. ] ([Only registered and activated users can see links. ])
2. Mod Rewrite2 - ($39.90US) - [Only registered and activated users can see links. ]
3. URL Rewrite - (23.00EUR) - [Only registered and activated users can see links. ]

Link Exchanging

1. Links Manager ($20.00US /mo)- [Only registered and activated users can see links. ] (This is great for the beginner however you will find out that you need to majorly adjust your pages manually in order to pread page rank throughout them otherwise you end up with 20 pages with no PR and 1 page with PR.)
2. Page Rank Finder - [Only registered and activated users can see links. ]
3. Link Appeal - [Only registered and activated users can see links. ]

Search Engine Submissions

1. Submit Express - [Only registered and activated users can see links. ] (A lot of people utilize this service. I don't utilize it)
2. Alexa - [Only registered and activated users can see links. ] ([Only registered and activated users can see links. ])
3. AOL - [Only registered and activated users can see links. ]
4. DMOZ Dummies Guide - [Only registered and activated users can see links. ] ([Only registered and activated users can see links. ])
5. DMOZ Instructions - [Only registered and activated users can see links. ]
6. DMOZ Resource Forum - [Only registered and activated users can see links. ] (This is where you go when you website doesn't show up in DMOZ after you have submitted READ THEIR RULES FOR ASKING)
7. ExactSeek - [Only registered and activated users can see links. ]
8. Google - [Only registered and activated users can see links. ]
9. Yahoo [Only registered and activated users can see links. ] (You must have an account)
10. Yahoo Directory Help - [Only registered and activated users can see links. ]
11. Yahoo Express Submit TOS - [Only registered and activated users can see links. ]
12. Yahoo Submit Help - [Only registered and activated users can see links. ] ([Only registered and activated users can see links. ])
13. MSN - [Only registered and activated users can see links. ]

ALink Reciprocal Link Checker ([Only registered and activated users can see links. ])
AMeta Meta Tag Editor ([Only registered and activated users can see links. ])
XML Sitemap Maker ([Only registered and activated users can see links. ])
RSS Feed Maker ([Only registered and activated users can see links. ])
Webpage Size Checker ([Only registered and activated users can see links. ])