You even get a wide variety of fuel options for your bicycle. I rode one to work every day for a few years, and my fuel of choice was oatmeal, which is healthy, cheap, and delicious (esp. w/ berries and honey).

Unfortunately, I changed jobs and cycling is no longer practical, but riding a horse is even less practical (can't really tie them to the parking garage in the city...). Maybe I'll get an e-bike and get back in the saddle.