6. Roswell UFO Crash Soil Sample
This soil sample allegedly came from the UFO crash site in Roswell, New Mexico. The US military officially maintained that it was only a weather balloon, however many conspiracy theory fans and other proponents believe that the military covered up a real UFO incident. If you are one of them, this red-colored soil should be an interesting item to collect.
http://www.amazon.com/Images-SI-RS-01-Roswell-Sample/dp/B000U5R4CM