The MonoMetro is basically a suspended, narrow gauge mono-path railway that was designed as a “possible solution to London’s transport problems.” Video after the jump.
The ultimate advantage of the low cost MonoMetro railway track is that it supports a broad carrying capacity range of vehicles spanning from Mass Transit (20,000 pphpd) Medium Range Tramway class (7-10,000 pphpd) to Personal Rapid Transit vehicles carrying 12 passengers per vehicle
[via FreshCreation – Londonist]