6. Invisible Destroyers!
The Theory The US must have had scientists as equally talented as the Nazis during the Second World War. They found a way to bend light around objects, rendering them invisible. Unfortunately, they experimented with this technology with the US destroyer Eldridge at the Philadelphia Naval Shipyard in October 1943 and things went spectacularly wrong. Eldridge was transported through space and time and reappeared at sea, with several sailors melded into the structure, and the technology has been used rarely since.
The Proof Little factual evidence, and absolutely no eyewitness reports or supporting statements. In fact, the whole theory seems to owe a large debt to the Charles Berlitz novel The Philadelphia Experiment, which popularised it.
The Truth It would make sense that, if the US had the technology to make ships invisible in the early 40's, they would have perfected the technique in the last 70 years. Also, a ship travelling through space and time and not one single sailor onboard coming forward to give a verified account of what happened? Hokum.