Several of the souped-up Samsung tablets Microsoft handed out to 5,000 developers at last week's BUILD Windows conference are for sale on eBay at prices as high as $3,500 (£2,226).

The tablets were given to developers to use while creating apps for Windows 8's new Metro platform of touch-enabled software.

One of the Samsung slates handed out to developers last week at BUILD brought in $4,000 (£2,557) at auction.

Of the five tablets currently listed on eBay, one has a top bid of $2,550 (£1,630), while two others are available at a "Buy It Now" price of $3,500 (£2,226). There is also an auction on eBay UK for one of these devices starting at £1,000.

Extra components, sensors and free 3G contract

The tablet is based on the Samsung Series 7 Slate, introduced in August, but sports several unique features and components, including additional sensors and ports, and a 3G-capable radio for wireless connectivity to the Internet. The tablet came with a free one-year 3G contract with AT&T.

The Samsung is powered by a 1.6GHz dual-core Intel Core i5 processor, the same CPU used in some of Apple's MacBook Air ultra-light notebooks.

None of the eBay sellers responded to questions about their listings, including whether they were developers or resellers, and if the latter, how they had obtained the tablets.

According to eBay records, more than a dozen BUILD-distributed Samsung slates have sold on the auction site since 14 September, at prices ranging from a low of $1,800 (£1,151) to a high of $4,000 (£2,557). The average price was $2,844 (£1,844).

Because Microsoft has opened the Windows 8 Developer Preview - the early build that's pre-loaded on the Samsung slate - to everyone and posted developer tools for downloading, some BUILD attendees may have decided that they could do without the free hardware, and have opted to develop on another device or on a standard desktop.

The standard Series 7 Slate will be priced at between $1,099 and $1,349 (estimated to be just under £1,000 in the UK), depending on the model, and will go on sale 2 October.