The glass could even...

The glass could even appear on Saab"s top-secret new premium hatchback. Due on sale in 2008, the Swedish model will be called the 9-2, and will take on the likes of the Audi A3 and BMW 1-Series. A spokesperson for parent firm General Motors explained that the clear roof would "fit perfectly into the Saab brand"s sporty image and aircraft heritage".

The 9-2 was originally planned to be built on the same platform as the Subaru Impreza, but that idea was shelved after GM sold its stake in the Japanese company. Now, the Saab will be assembled alongside the front-wheel-drive Astra in Germany.

Despite this, the Scandinavian marque insists the newcomer will be a "proper Saab", with specific parts and bespoke tuning of components, such as steering and suspension. It will also have a totally different look inside and out, drawing styling inspiration from the 9-3X concept car first displayed at the Detroit Motor Show in 2002.

That"s not the end of bosses" plans for the windscreen. Currently, the innovation is limited to non-VXR versions of the Astra Sport Hatch, as models with outputs of more than 200bhp can put undue stress on the larger glass area. However, the next-generation Corsa is smaller and will have less power than the Astra, so it"s an ideal candidate for the glass.

When the production model is unveiled at the British Motor Show in July, it"s unlikely to feature the new windscreen, but the option is set to be added to the Corsa line-up in 2007. And with the range-topping VXR version expected to offer around 190bhp, there"s nothing to stop hot hatch fans from looking skyward, either.