Why did the egg-shaped car cross the road? Because it cracked the secret to future mobility.

Unscrambling the solution to how occupants will get around in over-crowded mega-cities of the future hasn’t been easy for vehicle makers but a San Diego-based team of designers has hatched a solution.

The Eggasus is an electric-powered, fully-enclosed single-person car that can travel at up to 40kmh. It's based on an electrically-operated three-wheel trike, and when charged with ''green'' power produces no CO2 emissions.

Its US makers are pitching the Eggasus primarily as intra-campus transportation for the time being to enable students or teachers to get from one building to another quickly and without being exposed to the elements.

Avoiding public roads means there’s no need - at this stage - to install expensive and bulky safety systems such as airbags and crumple zones. The controls are extremely basic but in a nod to current trends it does include an iPod holder.

Its all-weather design means it could also be snapped up by buyers of the more traditional three-wheel power scooters favoured by senior citizens and people with a walking disability. The car, which is a finalist in the Sierra Nevada Innovation Challenge, is also being touted as an eye-catching promotional vehicle.

The Eggasus is expected to go on sale in the US later this year, when you’ll have to shell out US$5000 (NZ$6175). And, just like eggs, they’re cheaper if you buy them by the dozen. A two-seater is planned to go on sale next year.

-Fairfax Australia