You can see America's first Tent trailer (First, that I've seen anyway) designed for the Smart at
http://www.timeouttrailers.org
I remember this company from the early seventies. They made trailers for motorcycles. The Smart will easily pull anything that a motorcycle can pull. If they have been in business for over 30 years, they must be doing something right.
I find that the weight of their trailers are approx. half of the weight of the Europian trailers. Also Drag appears to be minimal
There is a guy here in Los Angeles that makes smart hitches.
The cargo trailer appeals to me when I think of luggage, bulky boxes, Skis, Surf-board, Kayak, dirty or messy items and I'm sure you can think of many more suggestions.
The combined length of car and trailer is no longer than the average car.
Sort of: Leave the 'Trunk' at home....... Take it when you need it.
The more I write about this, the more excited I get.
Smart Car... Smart trailer to follow
Donald LaFavor