The guys over at Hak5 have created a fun Graffiti Wall, this wall takes entries from the web and projects them on a huge display on their wall. The text display is just the beginning, games are planned in the future!
Give the wall a try!
Have a look at the code that makes it tick.
"Hey guys, this is the code I whipped together to make the Hak5 Graffiti wall. Toss in a projector and a webcam and it’s fun for the whole Internet. Now lets make it even better!"
http://hackedgadgets.com/2008/08/12/hak5-graffiti-wall/