Biking across the W&OD trail: fun. Biking across the Himalayas, on a unicycle, well, not so much. There's a guy in our neighborhood who has one of these "off-road" unicycles. We saw him a few times as we were taking Olivia home from day care. They look interesting, but I have a hard enough time staying upright on two wheels to even think about trying it with just one.