What is it?

From afar this red machine looks just like an R8, but move closer and it's apparent that there's a bit more to it than that. It's actually the e-tron, Audi's hint at how an electric supercar might work. With an electric motor powering each individual wheel it's perhaps the ultimate quattro, and all you need to do to drive it is plug it into the mains to charge up its lithium ion batteries. Do so and the e-tron will reach 62mph in 4.8 seconds and a maximum speed of 124mph, though drive it flat out everywhere and it'll be flat out (of power) before it reaches its official 154-mile range.

Why's it here?

A good question given Audi's own bumf suggests that only 0.035% of vehicles currently registered in Germany are electrically powered. The thing is we're reaching 'peak oil' production and the politicians are keen to tax us out of fossil-fuelled cars. The e-tron represents a test-bed for future technology then, and a glimpse into the future of motoring. Given how early everyone is in the process of getting electric cars to production the mere fact that cars like the e-tron can offer performance to equal and match conventionally powered cars is a good thing indeed. With further development we'll perhaps be driving cars like this sooner than later. If it looks and performs like this head-turner then we're all for it.

Show stopper or floor filler?

Given how difficult it's been to get a photograph of the e-tron without people clamouring over it then there's no doubting this electric machine's ability to attract attention. Aside from its obvious battery and electric motor powertrain Audi is using the e-tron to debut other future-looking technologies like 'Car-to-x' communication, which not only aids safety but benefits traffic flow. There's clever heat management too, as well as a neat infotainment interface. We're not too sure about the spoked alloy wheels, but otherwise the e-tron is among the brightest stars of the Frankfurt show.