Allow me to introduce you to possibly the most frightening piece of technology to emerge from the Cold War.
This is an Ekranoplan. It was designed by the USSR as a vehicle that had both land and sea capabilities. The idea behind it was that the huge engines created a cushion of air below it (similar to a Hovercraft but without the skirt) which it could then use to move around at tremendous speeds.
Luckily the Russian government decided not to back it due to cost.
Mentioned recently in the James Bond novel ‘Devil May Care’ when an Ekranoplan is used as part of an attempted terrorist attack on the Soviet Union. The Ekranoplan is destroyed by RAF Vulcan Bombers.
Reference: [Wikipedia]
Reference: [BBC (James May)]
Reference: [Devil May Care – Wikipedia]