I was having problems with Firefox crashing 7.10 yesterday, but it may have been something to do with the torrent file I'd just clicked on, since it was perfectly fine up to that point. I think it was trying to open it with a program not installed, as I left it at FF's default instead of choosing KTorrent.

It also wouldn't update for some reason. Gah. I only ever use Ubuntu at wireless hotspots anyway, but I had to hard reboot it twice as Ctrl+Alt+Backspace wasn't working, and neither were any other key combinations.