A vehicle that runs on air. It sounds like a fantastic idea, but energy is still needed to compress the air and the losses that go hand-in-hand with converting energy still have to be taken into account, just as in fossil fuel-based propulsion systems. Pros and cons aside, we still haven't seen air powered transport make an impact in the race to find economic, environmentally-friendly ways to get from A to B. Industrial Design student Dean Benstead thinks that compressed air does have a role to play in the future transport mix, and he's designed a working air-powered motorcycle prototype with a view to exploring the viability of the platform.