In Taiwan, the iPhone 4 just hit the market about a month ago and the supply is still pretty limited. Those carriers are issuing so called "pre-order ticket", which is limited to one per purchaser and has a exact time for purchaser to pick up his/her iPhone 4. It is designed to save people from waiting a long line at any carrier's POS and to prevent scalpers to suck up all the iPhone supply when available. However, such "pre-order ticket" is transferable and having zero out of pocket cost to get one. All you need is to send a request through your carrier's website and you'll get one. So, instead of selling actual iPhone 4, people in Taiwan are selling the "right to purchase", which is priced between 30 to 50 USD depending on the waiting time stated on such ticket. If you are a family of four, you can earned 200 USD in a day without any out of pocket cost.