I thought this might be useful for those on the scrounge for freely available impulse files. I'll add them to this post as people post more. Collections will be better than individual ones, or it might get a bit out of hand.
Sperimental - GuitarAmpModeling.com • View topic - [LAST UPDATE] Official Sperimental Impulses Pack
GuitarHack - GuitarAmpModeling.com • View topic - Guitar Hack's Impulses - full pack
RedWirez Free - Red Wire Impulse Responses | Free guitar speaker cabinet IRs
ReCabinet Free - Recabinet Cabinet Impulses | Free Musician's Resource
OwnHammer Free - OwnHammer.com - Public Beta Redux
Catharsis - http://www.ultimate-guitar.com/forum....php?t=1542877
Mattayus - Zilla Fatboy