You know that old chestnut about F1 cars generating enough downforce to be able to drive on the ceiling?
Well, this theory so beguiled former Audi engineer Roland Gumpert that he used it as the guiding principle on which to build his supercar.
This is the daftly named Gumpert Apollo, the latest car to come knocking on the door of the exclusive supercar club.
A road-legal racer, the Apollo is designed with downforce in mind. Weighing in at just 1,100kg thanks to a carbon-fibre monocoque, the Apollo generates 1,500kg of downforce at 200mph - theoretically enabling it to drive upside down. We're not volunteering to test that theory though.
The speed comes from a twin-turbo version of the Audi RS4's 4.2-litre V8, producing 650bhp and 627lb ft of torque.
That's good for a top speed of 224mph, which would presumably be even higher if it wasn't for all the downforce.
There's more evidence of Audi's influence - though the German company didn't play a direct role in the Apollo's development, it does have subsequent patents on the car's development - in the gearbox: a six-speed sequential dual-clutch unit.
And although the cabin may look barer than a Page 3 model, Gumpert has found room for such creature comforts as satnav, air conditioning and a rear-mounted reversing camera.
Gumpert says the Apollo is production-ready, with starting prices in the region of £190,000. The only problem is that Tom Ford drove a pre-production Apollo almost two years ago, at which point Gumpert said the first models would be on the road by the end of 2005.
But although there are reports of a few Apollos knocking around Monaco and the like, we've still not been invited to drive one. It's enough to drive you up the wall... and onto the ceiling.