git-svn
I'm getting to the point where I'm using git-svn in preference to the plain Subversion client for every project I actively work on. I don't use most of the features, but it's worth it just to be able to do git log, git svn log or git log -u and see the commit log without needing to ask the server. Remember how awesome it was the first time you ran svn status or svn diff and got immediate results, as opposed to cvs update or cvs diff -u? This is the natural next step from there.
Being able to commit while on a plane is pretty cool too (I did that last time I flew from SFO-AKL), git stash is handy, and git commit --amend is very nice, but git log is git-svn's killer feature for me.