Great, thanks for the info.
Yeah, the problems started around the time I put 3rd party memory in. But then I took it out and I still got kernel panics.
I've:
taken machine back to the way it was when I bought it (hardware wise)
formatted and reinstalled panther
reseated memory
zapped pram
repaired permissions
fsck'd
and well, nothing seems to fix it, so I guess I'm off to the local repair shop