A lot of the forums I use seem to have some form of for sale sections normally along the lines of what the forum is about. It could be a place to sell things like games, consoles, peripherals etc.......
Don't know if any of you guys have seen it before but if you go to a site called AV forums they have an arcade like here but they also have a casino to play in.
1. Katapult
2. Fling a man in a jump shoot as far as you can using an old seige weapon :)
3. http://www.spikedhumor.com/articles/38527/Katapult.html
4. Not sure......