Boku is a programming environment for tots. It comes from Microsoft's Creative Systems group, and the project is lead by Matt MacLaurin. It will come out for PC and XBOX360 one day - it doesn't even have a website yet though, so that day may be a way off yet.
I go on about programming for kid's alot, but Matt really gets it, and is doing something about it that looks amazing. I can't wait to play with this stuff and get my kids involved.