I uninstalled Limewire last night, but I don't think that was the problem. I looked at my system specs and suddenly I have 384 MB of RAM, when I normally have 512. OSX is normally rock solid for me (no stripes or strange trash messages), so I'm thinking my problems might be related to a messed up memory card. I added 384 MB of RAM to my original 128 last year, so one of the replacement 128s might have gone bad. Very strange indeed...