What is it?
I saw this in the parking lot of the hotel where I'm staying. Inspection: yes, it's the chassis of an early 1970s VW, with motor and transmission in place. The motor appears functional. It's connected to the gas cans. Yet, this is a trailer. Why? (Hint: it's parked next to a new Toyota CRV electric car.)
Answer: The owner has a nice new Toyota CRV electric. He extolled the virtues of the electric, its greenness, and the tax breaks and free charging options. But, it only has a 120 mile range, and sometimes he needs to drive longer distances on the freeway. This is Utah, after all.
So... the VW trailer. When in need, he puts the trailer in 4th gear, and turns on its electric system. The throttle is stuck full open. He pulls it to get going put, put put put... Then, the trailer pushes the car along. What if he needs to slow down? No problem, he hits the regenerative brakes on the Toyota, so now the VW is also charging up his batteries!
American ingenuity is still alive!
I did not ask if the highway patrol was aware of just how the trailer functions. Or the DOT, EPA, NHTSA, etc. etc.