Step #1: figure out how to get Linux back. A recent upgrade of OS X had wiped the boot sector.
Cmd-Option-O-F
boot hd:2,yaboot
That did it. (note to self)
Then did some yabootconfig/ybin/etc stuff that should make it automatic now. We'll see.
Anyway, for the short, scary period I was in OS X without Debian, I accidentally clicked this big green box in iChat and I started talking to sherm
I come back in Debian and everything's zippy. Awwww.... what a relaxing feeling.