Evening All

I'm possibly looking for something that doesn't exist but I wondered if anyone uses a utility which can create a bootable USB HD, but the loader needs to be able to read iso's on the fly. The idea being that once the loader is on the USB HD, I can copy new images onto it and the loader will dynamically read an Images folder and build the list in the loader screen without having to recreate the loader on the HD.

I've had a bit of a Google and have come across a couple of things which 'might' do this. I just wondered if any of your are actively using anything like this already?