Fraudsters launch auctions on eBay or TradeMe with very low prices and no reservations especially for high priced items like watches, computers or high value collectibles. They received payment but never delivers, or delivers an item that is less valuable than the one offered, such as counterfeit, refurbished or used. Some fraudsters also create complete webstores that appear to be legitimate, but they never deliver the goods. In some cases, some stores or auctioneers are legitimate but eventually they stopped shipping after cashing the customers' payments.
If you didn't already know this, it's good info for you guys, so be aware this stuff is out there!