Sniffex

The Sniffex (later SniffexPlus and HEDD1) is (at least according to its manufacturer) a bomb-detection device invented by a Bulgarian engineer. It looks suspiciously like a glorified dowsing rod. It also doesn't work as a bomb detector, though it may be somewhat effective in enriching the people who sell it to unsuspecting clients. It was tested by the US Navy (the Naval Explosive Ordnance Disposal Technology Division) in 2005 who found out that "The SNIFFEX handheld explosives detector does not work."

James Randi noticed the Sniffex website in August 2005 and invited the CEO of Sniffex, Inc. to submit it to the million-dollar challenge.