Our server for Software Design and Documentation failed over Halloween weekend. I've just finished migrating all services from that box to others within my dorm, and I am very thankful for my team's choice (heavily influenced by me) to chose git as for our version control.
A little background on git: it is the distributed source control system used to control projects such as the Linux Kernel or X.org. The distributed nature ensures that each clone of a repository contains the entire revision history of the original.
To make a long story short, restoring our revision control system was easy as cake. Had we used subversion, all changes checked into the repository since the most recent backup would have been lost.