Here's a new and interesting take on the pusher trailer concept:
It has drive wheels, 900W of solar, and 80kWh of batteries! It appears some kind of connection senses the towing and braking forces at the tongue to power or regen brake the drive wheels. Something like the mechanical action of typical trailer surge brakes.
The eStream is a proof of concept for how the classic travel-trailer experience can be updated for the EV age.