I've had this happen on my system. I was using Feisty Herd 1 and my network went down (not unplugged cables, the actual network) and then my system hardlocked. I couldn't do anything and had to restart my computer to get it to work.
-- System crashes if disconnected from network https://launchpad.net/bugs/78841 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
