WARNING: Much of this is a little weird, and may be of limited use to many "classic" fantasy gamers.The Sletchweb - My website, has all the rules I've written that I've felt inclined to put in it. I've got more material but am limited in terms of available time and effort.
Some is pretty "Work in Progress" - I was going to be running a Supernatural Investigation game that ended up falling apart (so my Psionic Powers are 3/4 complete), and the Modern Equipment is nowhere near as expansive as I wanted it to be.
About half to 2/3 is playtested (Modern equipment, classes and most the feats - most of it except the Stargate and Psionics stuff, since those games didn't happen).
There's also a bit of GURPS Fallout stuff there, should you be interested in such things (I'm running it so the new roleplayers only had to learn one system at a time - there was a GURPS Transhumanism game already planned, and Fantasy Craft is just so different from GURPS).
(EDIT) Note: Everything is under the Creative Commons Attribution license - which basically means feel free to use it, just make sure to attribute it to my site if you post or link it elsewhere (rather then copy/paste wholesale without saying where you got it).