keep my life in a subversion repository. For the past five years, every file I've created and worked on, every email I've sent or received, and every config file I've tweaked have all been checked into revision control. Five years ago when I started doing this, using CVS, people thought I was nuts to use revision control in this way. Unlike CVS, subversion has reasonable handling of directories and file renaming, which is more than sufficient reason to switch to it if you're already using CVS, and most of CVS's other misfeatures are also fixed. But subversion still has its warts, such as an inability to store some file permissions and its need for twice as much disk space as you'd expect thanks to the copies of everything in those .svn directories. These problems can be quite annoying when you're keeping your whole home directory in svn.