2. Cadillac Converj

* Five show disappointments * What left us feeling let down? * See the pictures...

2. Cadillac Converj

Eager to prove that the technology behind the headline-grabbing Chevrolet Volt can be applied to other types of car, General Motors unveiled the Cadillac Converj concept car at the Detroit motor show.

It is a great-looking car and equipped with ground-breaking technology, so what's the problem?

Well, while GM is making hay with the headlines surrounding the Chevrolet Volt and its Voltec powertrain, there's a feeling that other manufacturers (Toyota and Lexus in particular) might trump them by getting better products to market quicker.

Still, the technology is sound. As with the Volt, the Converj has a 40-mile range on battery power alone, which GM officials say can be extended 'by hundreds of miles' by power from the engine.

The Voltec system delivers 273lbft of pull, 163bhp of power and has a 100mph top speed. It can be charged in three hours from a 240V socket.

Fuel saving is further enhanced by an all-glass roof incorporating solar panels and an aerodynamically efficient body shape.

The wing mirrors are also replaced by rear-facing cameras, and the wheels are sculpted to improve airflow.

The car sits on 21-inch wheels at the front and 22-inch wheels at the rear.

Insiders say that although its appearance is close to how a production model would look, albeit without some of the more outlandish details, the Converj is still several years from appearing in showrooms.