Felix Salmon on an artwork, by Caleb Larsen, that "is so commercial that it can’t be collected." The purchase contract apparently includes the following:
"Artist has created a work of art titled 'A Tool to Deceive and Slaughter (2009)' ('the Artwork') which consists of a black box that places itself for sale on the auction website 'eBay' (the 'Auction Venue') every seven (7) days. The Artwork consists of the combination of the black box or cube, the electronics contained therein, and the concept that such a physical object 'sells itself' every week."
At his own website, Larsen explains: "Every ten minutes the black box pings a server on the internet via the ethernet connection to check if it is for sale on the eBay. If its auction has ended or it has sold, it automatically creates a new auction of itself. If a person buys it on eBay, the current owner is required to send it to the new owner. The new owner must then plug it into ethernet, and the cycle repeats itself."
UPDATE: More from Regina Hackett.