One other neat thing that I saw at the summit last week was Minecraft running under the control of a TouchDevelop program. TouchDevelop is a great way to get playing with writing code.
And there's a neat little competition running as part of the Imagine Cup that you might like to have a go at if you are a bit younger than me. Essentially you get to re-invent/re-imagine the classic Breakout game. And there are big money prizes. Find out more here: