I rather fancy the Astral; I like the gyroscope concept and I could drive it along the canal as well as on the roads.
I was thinking today, as I pedalled along the canal towpath and watched the swan gliding serenely along knowing that under the water its legs and feet were going like billy-oh, why aren't there more efficient ways of travelling on water using human power?
Yes I know there is rowing your boat and paddling your own canoe (or kayak!) - sailing being impractical on a canal - but those are rather wet, splashy and primitive. I picture something vaguely like a recumbent but in a boat, and while you sit in comfort, warm and dry in a nice enclosed capsule/cockpit, coffee by your side, you are cranking quite gently on pedals which drive a paddlewheel or propeller (or something else - I know very little about efficient propulsion in water), well-shielded from the driver/rider/boater so there's no chance of getting wet.