I came across these two fancy BMWs at the Mecum Auction and show in Orlando, Florida. They are called Isetta Cabriolet 300s by BMW in 1957. Tiny and cute. It looked like only one back wheel, but I think they had two small wheels close together.
Did you see there are no doors on the sides? How does one get in? See the hinges on the right front, that is where the entire front opens up.
Here is another in blue and white if you prefer. They are even convertibles!