I was running FoldIt and had my net connection drop out midway.
The program froze... then segfaulted.
I tried to get it to restart and it continually segfaulted... then I realised the net connection was down and got that back up again and the app was able to start again.
Obviously, I got it working again - but figured it might a) help somebody else that's confused and b) prompt somebody to write a slightly better graceful failure mode than an explosion, losing all my efforts... ;)
Gotta coredump if anybody wants it... going cheap! ;)