A story is reported on Slashdot regarding a Steam for Linux bug that accidentally wipes out all of a users' files if the Steam directory is moved.
"I launched steam. It did not launch, it offered to let me browse, and still could not find it when I pointed to the new location. Steam crashed. I restarted it. It re-installed itself and everything looked great. Until I looked and saw that steam had apparently deleted everything owned by my user recursively from the root directory. Including my 3tb external drive I back everything up to that was mounted under /media."
- Says this unfortunate users' bug report.