Hey... why don't we all get together and see if we can compile copies of every version of ICQ ever released? I'll even offer to host the execs!
I found a great site a couple years ago and now have Windows 1.0, 1.1, 286, 386, 3.0, 3.11, NT 4, et al. Then I set up an old box dedicated to nothing but running these OS'. Pretty cool find, actually. Then again, i'm a recent-history buff...