Bizarre little item here taken second-hand from the book Spycraft: The Secret History of the CIA's Spytechs, from Communism to Al-Qaeda by Robert Wallace and H. Keith Melton, by way of Gizmodo.com. During the Vietnam War, the CIA used boats that looked somewhat like native coasting craft to deliver "assets," presumably to Communist-controlled areas. But should a purposeful-looking patrol boat appear, the spy-boat's crew would ditch the rig and superstructure, revealing the large speedboat beneath the disguise to make a quick getaway.
What won't those spooks think up next, huh? Well, as Gizmodo notes, the concept has roots in the Q-Ships of the Second World War, and pirates have been disguising their vessels to masquerade as innocent traders probably for millennia. But I'll bet that few such preceding Trojan sailing boats were so dead-giveaway-undercanvassed as the CIA boat appears to have been.