Seriously. Caleb Larsen's "A Tool to Deceive and Slaughter" isn't quite as menacing as it name makes it out to be, but it's a finicky little guy: 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 10 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 being constantly auctioned and purchased. You can view the current auction at http://atooltodeceiveandslaughter.com/.
The current auction ends in five days, has seen 12 bids, and is currently at $US4250. The piece has been in circulation since 2008.