I guess I haven't been putting my Palm on its charging cradle often enough recently, or it's been turning itself on in my pocket a lot. I pulled it out of my pocket a little while ago to sync it before the weekend, and it wouldn't turn on. Popped it on the charger, and turned it on after a minute... to a "welcome" screen as though I were turning it on for the very first time. All my stuff was gone.
Can't tell you how glad I am that Palm makes it so easy to back up your whole handheld to your computer... and to restore all of it to the handheld if it's been wiped, or to another new handheld if it's been replaced.
It'll take a little while, but all my stuff is now copying wirelessly over to the Palm.