http://www.planetdan.net/blog/2007/06/missing-piece.htm

Get it? Because Cheney’s EVIL! What a gas! Even without the puzzle effect, it’s like “Hey Cheney! Do you think you could try to look a little less like a comic book villain when you get your picture taken? What’re you, trying out for the Phantom of the Opera or something? Sinister looking mother fucker…”