Caleb Larsen's "A Tool to Deceive and Slaughter" isn't quite as menacing as its name makes it out to be, but it's definitely a flighty little fellow: it continually creates new eBay auctions for itself via a built-in Ethernet jack.
No owner is quite good enough for this big-headed piece. Larsen's "Tool," a shiny, black cube with an Ethernet jack, pings a server every ten minutes to determine if it is listed for sale on eBay. If it's not, it creates a new auction. Mind you, this isn't only a conceptual function of the piece; it really is constantly auctioning itself and being purchased by new owners. You can view the current auction at http://atooltodeceiveandslaughter.com/.
The going price for the current auction, ending in five days, is $4,250. The piece has been in circulation since 2008.