Part 1: I took a projector that was too dim for front-of-classroom use and mounted it on the ceiling. No big technical challenge there . . . just a 15' VGA extension and it's set.
Part 2: In order to move the mouse in real-time on the table, I bought a UV Pen and a UV sensor/bluetooth module. The pen cost $12, and the sensor I bought at WalMart (in the form of a $40 WiiMote). I didn't want to have to change batteries on the WiiMote, so I ran power up to it.
Now I have a digital whiteboard table in my classroom--for its first voyage I did a little photo editing and was delighted with the results. Yay!
More posts about WiiMotes as digital whiteboards on the EdTech20/20 Blog from May 0f 2009.