Harry Potter, where is your PoV wand?

I found out about a game that was done at Microsoft's Puzzle day involving everyone's favorite book, Harry Potter and his wand.  All wand jokes aside, Nathan Pooley, appears to have created the wand and shows how to build a Harry Potter Point of View (PoV) wand.  It detects if you did the correct spell by an onboard accelerometer.  Depending on the movement, it "casts" different spells.

The source code and the PCB diagram can be found at his site along with an FAQ.