I am intrigued my the recumbent tadpole such as WindCheeta and Greenspeed, etc. All who ride them call it a blast!
However, there may be an easier way to achieve some of the advantages of 3 wheels without quite going that far. Have you ever seen a fixed or lowerable 'landing gear' added onto a 2 wheeler? I see in my mind, roller blade wheels that are near or aft of the rear wheel of a 30 or 45 degree recumbant. Advantages, low and zero speed stability and hill climbing.
What do you think?
Any recumbant riders in my area?