At the end of performances of his Broadway play “Cyrano de Bergerac,” Kevin Kline, who starred as Cyrano, the cavalier poet with a huge nose, auctioned his prosthetic proboscis, which he and his costar, Jennifer Garner, autographed (Mitchell, Dan, “This Time, Santa Has Been Too Naughty,” New York Times, December 9, 2007) to benefit Broad-way Cares in its fight against AIDS. An English auction was used. One night, a television producer grabbed the nose for $ 1,400, while the next night it fetched $ 1,600. On other nights it sold for $ 3,000 and $ 900. Why did the value fluctuate substantially from night to night? Which bidder’s bid determined the sales price? How was the auction price affected by the audience’s knowledge that the proceeds would go to charity? Why?