Called Naturcar, it's not pulled by a horse like a modern-day apple cart, but powered by a horse. For now the concept is nothing but computer-generated video and renderings, but here's how it seems to work:
With the horse in back standing on a conveyor belt, driver and passengers sit up front. Instead of whips to motivate the horse, Naturcar uses electricity to power motors on the belt that gets the horse moving. If the horse stops walking, the belt nudges it back into action. The same belt moves the horse's "exhaust" into a holding area beneath the car.
Unlike its working ancestors, Naturcar's horse would be air conditioned, continually fed and watered and its temperature constantly monitored. The aforementioned electric motors could even be used to pull the car up hills instead of overexerting the horse.
Perhaps if the horse were merely being used as a means to keep the car's batteries charged this might make at least some sense. But horses take too much maintenance, upkeep and food to make much economic or ecological sense as mainstream automotive engines.
Check out our gallery of photos from Fleethorse or watch a CG video of the Naturcar.