From Mojobojo's Blog:

So my goal was to get an application going for extracting assets from the XEX's for the 360. After a couple hours in front of the beloved Hex Editor and a while in my trusted C++ Compiler I got an application going to do just that. Remember that in order to use this you NEED to decrypt and decompress the XEX first (xorloser's XEX tool FTW).

Usage:
Info on the app: xexextractor -i
Extract: xexextractor -e "In XEX" "Out Path"
Official Site: http://mojobojohax.blogspot.com
Download: here