Laughing all the way to the Banksy

They came in their hundreds, and queued overnight, for the opportunity to pick up a print by controversial graffiti artist Banksy for £100.

Now some of the art fans who braved freezing weather outside his temporary "grotto" in Oxford Street have made a killing by auctioning them off.

The limited edition black and white images, called Flag, were originally put on sale on 18 December in aid of a charity which provides cataract operations for children in Bangladesh. They sold out within two hours, but scores of them have since been put up on eBay, raising over £400 apiece.

One print had attracted 23 bids and raised £410 with two hours of its auction to go - more than quadrupling the owner's investment. The item was on sale from an address in South Ockenden, from a seller known as "magnetandsteel_reillyone".

The sales reflect a trend for shoppers to make a profit on rare items. The Nintendo Wii console was selling for four times its retail price on eBay because of scarcity in shops.

The eBay auctioneers selling on the Banksy prints are anonymous but artist Carlo Raffa, 33, from Brighton, who was first in line to buy one, said he planned to sell his on eBay.

He was disappointed by the piece as it was "machine-printed with no signature or number".

But another buyer, Cathryn Taylor, 24, from Tooting, said: "Banksy is anti-capitalist and wouldn't want people to buy his pieces just to sell on for profit."