I think I've figured it out, and it has nothing to do with Stuffit after all. The system is simply overheating. I turned it on yesterday evening and everything was working just fine (Shufflepuck, Fools Errand, Gunshy, DotC, etc.). I went downstairs and came back a little under two hours later and all those programs were crashing again with Illegal Instruction errors. The upper left corner of the case was really hot, but the HD case was cool. So just to make sure it wasn't the HD I disconnected everything, booted from a System Disk, tried to run Gunshy and BAM! it crashed. I left the Mac off for a few hours and now everything is working again.

I'm surprised the Mac overheats so fast. True I have the brightness turned up all the way, but still. The room its in is pretty chilly (66 degrees) and it's next to a window where its 18 degrees outside, so it's not like the room is a sauna. Maybe I have a defective part on the board? I cracked open the case to see if everything was seated properly (everything was a tight as it could be), and I noticed the the vertical component board had some heat marks on it like it had gotten too hot at one point.

I guess I need to look for a replacement mac. Maybe a nice SE or SE/30. In the meantime I guess I can point a fan at the case, but the HD fan is already way too loud and I really don't want to add another.

Tempest