[tom_]

If there's one of you, whatever, it's your problem.

If thre's two of you, I might be so bold as to suggest it would be worth giving SVN a try. All the usual handy version control system stuff that makes collaboration easier, but the mental model is simpler than git (with all the things you can imagine that might imply), and you've got a handy escape hatch, in the shape of svn lock, for non-mergeable binary files. Great for PSD files and so on.

(Another thing about SVN that's different from git: working copy disk usage is proportional to size of HEAD, not size of repo. You can reasonably use it for distributing binary builds to non-programmer team members, for example.)