Rinspeed Senso

As well as building wild models such as the Chopster, Rinspeed has been experimenting longer than almost any other small car maker with the possibilities of natural gas power. This is due to the wide availability of gas in Switzerland - and when fuelled this way, the Senso's 3.2-litre Boxster S engine lowers CO2 emissions by a full 30 per cent.

Just as important as the eco-friendly unit is the "smart surface technology" built into the windscreen. This film is made up of hundreds of small square cells that bathe the cockpit in a stimulating glow of green, blue or orange light, depending on your mood.

The trick is aimed at improving the driver's state-of-mind, and is accompanied by a soothing soundtrack. Scented air is then wafted through the passenger area to complete the feeling of well-being. Recaro sport seats for three, as well as gleaming 19-inch chromed wheels, add to the unconventional driving experience.

Other road users, however, don't take too well to the newcomer's crazy appearance. For the most part, the Senso is greeted by other motorists with looks of disbelief. Maybe a spell sitting in the soothing light of the cabin is just what they need.