Pay for a button on this website and you`ll get back twice of your initial payment when another 2 buttons are bought on your column.(at least this is what i`ve understood) It`s not my website, but i bought advertisement in there and i thought it would be cool to share it with you. http://www.dodouble.com
lots of these lately. seem to be on the downswing, though. maybe good for the first few people who jump on, but someone usually ends up paying a lot for an ad with little traffic probably. -kpaul