One of the new blogs I've started reading, The Daily WTF, has a great entry today: The Spider of Doom

Beware of what UI and chrome you put into your web forms as verbs - GoogleBot will go through each link and if "Delete" or some other destructive entry is there, Poof! Because the bot is going to go through everything that looks like a link.

I worried about this w/ Google accelerator (or whatever that was) because it would prefetch pages for you based on what you're currently reading. Eeeeeyeah, maybe you don't want that if some of those links are destructive.