All off topic discussions go here. Everything from the funny thing your cat did to your favorite tv shows. Non-programming computer questions are ok too.
I use subversion. We use it at work. Before that we've used CVS (over ssh) and VSS (evil - do not go there) and MKSRCS (on dos, over netbios, on a "Lantastic" network... with a 386 w/ 4M ram as a server).
You should include an 'Other' option in the poll, I use Bazaar-NG (bzr). Although, it does get a bit annoying at times and I may end up switching to SVN.