They can move you along at speeds upwards of 20-miles an hour for distances up to 30-miles at a stretch. They're computer controlled and host features too numerous to list. They're e-bikes, electrical power assist bicycles. You still do the peddling but when the going gets harder on hills, for example, the electric motor kicks in to carry the extra load.
A recent U.S. competition was won by Seattle's Teague "Denny":
But the Denny is just one of a horde of contenders. Motors by Yamaha, automatic gear boxes by Shimano, designs by Audi, there seems to be no limit to innovation and creativity.
So many terrific designs, so many brilliant ideas. Now, if someone can just incorporate as many of the greatest features in one bike, we might all be lining up to get it.