US pop star Britney Spears is selling herself on eBay. But the Piece of Me singer isn’t hard up for cash; she’s auctioning an autographed portrait of herself for a good cause. Spears and her family has donated the 1.52-by-1.22-meter oil painting to the Promises Foundation. The foundation provides health services to low-income women and their children. Bidding started at $10,000 and ends September 20. The winner also gets a letter of authenticity from the artist.