They've been dropping in price, but 3D printers still cost enough to make all but the most enthusiastic buyers balk. That doesn't mean that you can't get your hands on a 3D printed trinket however: there are already a few options, but eBay has just joined the crowd with a new iPhone app called eBay Exact. The app features only a few items 3D printed each from MakerBot, Sculpteo, and Hot Pop Factory that can be customized and purchased directly from the app. Most of what's available is jewelry, though Makerbot is offering an "exclusive" watch and tape deck MP3 player, and you can design a custom iPhone case from Sculpteo. Options include color, material, engraving, and more. The store is currently labeled as a beta, and it looks like eBay is just wading into the waters at this point — not unlike its approach to same-day delivery service eBay Now.