The most aerodynamic possible motor home; the first is 7x24ft and has a fineness ratio of 3.42:1, the second is 8x40ft for a ratio of 5:1:
Here's a design for a small trailer that follows the Template except that it only tapers on the sides, like the Tropfenwagen.
The closest commercial product is the Airstream BaseCamp. Here's why you want an electric screw jack retractable trailer tongue:
