The idea of a tilting trike with a fixed rear drive section has been getting a bit more press with the Carver and Clever and the VentureOne, but I saw this one, called the Trilean, for sale on eBay based on a Honda Gold Wing and according to the description, it was built in 1998, so it precedes the others by a number of years. Before you criticize it on aesthetic grounds, remember, this looks like a homebuilt creation by someone who thought it would be a cool idea and then actually built it.
Power is from a 1520cc Honda Gold Wing flat six, the differential is from a BMW 320i, steel tube frame with a custom designed fiberglass body. The tilt is computer controlled, but he says it needs "further development work" with some type of programmable logic controller. Not surprising, since I think that would be the most difficult part of getting something like this to work right. Of course, now that those other trikes are doing it, there might be a better possibility of making it work.
Interesting idea and just needs a bit of tinkering (or maybe a lot) to make it work right but for a garage project, it's pretty neat.
Link: auction has ended