I've recently switched to using git for source control, after svk screwed up a merge on me. Unfortunately, I'm still interacting with a Subversion repository until we convert entirely to git.
One thing that git does really well is merge, so naturally when I need to backport something from our devel tree to our stable release tree, I want to use git. Unfortunately, git-svn doesn't seem to handle branches nicely. Or, maybe it does and I'm just missing something. At any rate, I could check out using git-svn, but pushing the changes back to the branch seemed to break, so I had to hack something. Here's how I got multiple branches working.