What's said to be early iPhone prototypes have gone on sale on eBay where bidding is currently up to $2270 - around £1600 - with 56 bids.

There are two handsets in the auction lot, one of which is in working order, running what's described as a "beta OS".

Modestly described as "quite rare and collectable" (if they are the real deal), the seller points out that neither unit says "iPhone" and from research on the serial numbers, they are pegged as manufactured about 6 months before the phone's launch.

Unlike launch models, the working phone has a matte plastic screen and the seller notes that it has several "interesting subtitles" that alternate on the screens.

These include "Skankphone", "Nine parts perspiration" and "Say hello to the Newton MessagePad 3000". Apple's MessagePad line ended with the 2100 in the late 1990s.