We from TheEthosProduction have made a game called four in a row. I don't know if this exist in other contries but it exist in Sweden any way. It took us over 20 hour to build it and it was not that funny because we knew exactly how we should wire the redstone. All was about to have time to build, but now it is finally done and we are so happy that it works :) We are from sweden so we have a swedish video there we show how it works and little on the redstone, but i can make an english if you guys want it if you don't understand how to do it :)

http://www.youtube.com/user/TheEthosProduction?feature=mhee