@b0rk
Up to date backups, and - as another person mentioned - keep everything you can in git.

It's easy to be fearless when you always have an undo button.

Edit: Besides, if you are seriously worried about accidentally deleting files, you should be just as worried about a hardware failure or software bug doing it for you. It probably means you don't have backups or don't trust them. That's the first thing you need to fix.