While our thoughts on all things iPhone may be focused elsewhere, an unusual Apple prototype of its fourth phone iteration has caught our attention on eBay. On the back, you can see the same curious logospied on experimental hardware as far back as February 2010 and as 9to5Mac notes, it doesn't pack the screws along the bottom edge, making it ever so slightly different to the final model. The phone (model number N90AP) also runs Apple's software testing framework, Switchboard, which is still happily ticking along on this particular prototype. Bids start at $4,500, or there's a Buy It Now price of $10,000 -- if you must have this obscure slice of Apple history.