I've had the desktop computer running non-stop for almost two months now. It's got Ubuntu 10.10 running and I let the updates run every now and then.
Today when I was about to start working on some flex code, I noticed update manager had gone zombie in the middle of upgrading the 'mount' package. I tried stopping it and restarting several times and it failed whatsoever at stage preparing replacement for package mount<blablabla> so I decided it's time to restart the heap of junk for once. When I restarted I got "General error mounting filesystems," and the maintenance shell. After wondering about it a bit I noticed that the mount upgrade had left /bin/mount without the execute bit set and thus the system could not run it.