Undo! Undo!

I think the Staples commercials with the Easy button are stupid, but I've decided life would be much improved if people had Undo buttons. Like the use in word documents, you'd only be able to undo so far back into the future, but at least if you made a mistake and immediately realized it, you could undo and try again. The world would be better for it.

... as long as it wasn't used for evil, as most useful things seem to be destined for.