Stumped about what to give that special someone this Christmas? How about some rhino poop?

The International Rhino Foundation is auctioning separately on eBay four pieces of dung from the endangered species and will use the proceeds to fund conservation efforts.

The pieces come from four of the five types of rhino: white, black, Indian and Sumatran.

The Javan rhino is so rare that a sample could not be collected.

• Click here to bid on rhino poop. Auctions end Sunday, Dec. 9.

Each piece is dried, mounted in a clear trophy case and marked with the type of rhino that produced it.

The auction ends Sunday and as of Thursday afternoon bidding had been light, with the top bid for Sumatran rhino poop standing at $500.

Black rhino poop was standing at $255, Indian was at $250 and white was at $122.50.

The foundation, which is based at the White Oak Conservation Center, says only about 17,500 rhinos remain in the wild with another 1,200 living in captivity.

On its Web site, the International Rhino Foundation is promoting the auction with the catchy tag line, "Buy endangered feces to save an endangered species!"

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