In my book Constant Vigilance, I suggest an alternate interpretation of certain historical events. I considered an industrialist that work with the US government and fell out of grace. After he stopped working with the black ops programs with the government he started driving around in an automobile that filtered all the air that the occupants inhaled. This filtration system included eliminating any possibility that bacteria could get inside the passenger compartment. The book's position was that the industrialist was not a germaphobe, but a person that knew it was possible to to kill someone by releasing material in front of a driving vehicle that made its way to the occupants inside.
Howard Hughes had such a vehicle and it is currently up for auction at Barrett Jackson. The car is a 1953 Buick Roadmaster and it was the last car Hughes ever drove.