At the Vienna Motor Symposium, what's billed as "one of the world's most important power train events", German volt-heads FEV brought an electric 500 with a Wankel range-extending engine (the setup is called LiiON Drive).
The rotary engine is mounted in place of the fuel tank, which has shrunk to 12 liters / 3.2 gallons. It gives the little city car an extra 190 miles of road to travel on top of its 50-mile electric range.