This picture from 1966 shows world champions Jackie Stewart and Graham Hill flying their BRM Formula 1 cars during the German Grand Prix at the Nurburgring. Flying is something that cars can sometimes handle, backflipping on the other hand is dirt bike and jetski territory.
The backflip is a key element in Freestyle Motocross. Travis Pastrana, the man behind Nitro Circus, is a pioneer of this stunt. He was also the first to perform a double backflip in competition, which he did at his last chance to score a gold medal at the 2006 X-Games. Not a bad performance under pressure:
Cars do the occasional backflip too. In 1993 Christian Fittipaldi actually flipped his Minardi Formula 1 car and crossed the finish line in a rather special way:
The most spectacular fourwheel-backflip that I know was performed by Formula 1 driver Mark Webber, but not in an F1 car. At the 1999 24 hours of Le Mans, his Mercedes-Benz CLR had a flat underside, which helped suck the car to the ground in corners. The problem was that air could also get caught under this flat bottom at speed, and literally lift it off the ground, for instance when closely following another car or over bumps. This happened to Webber, who got launched and flipped straight for the trees… Well, just see for yourself: