Stopped giggling yet? Then click the pic and get a closer look at this ingeniously insane monster motor unicycle from Holland. There are currently only 50 Wheelsurfs in existence and buying one will set you back around £3100 in Europe but, boy, what a way to get about! From the look of things, the main point is to put a huge grin on your face and attract lots of stares while getting from A to B. Admittedly, it's not the most eco-friendly way to get around as it uses unleaded petrol, but it's certainly better than a big gallon-guzzling car. Get the full low-down on how it works - the secret is two frames, an inner and an outer one - over at Wheelsurf's website.
Just being picky, but it's a monocycle, not a unicycle (if you sit inside the wheel it's a monocycle, on top and it's a unicycle...).
Might actually be relatively ungreen assuming it most likely uses a 2-stroke engine which will often have far worse emissions than a small car... sad though as they are crazy machines (though why not just get several good bikes for the same price and choose the one suitable for your journey).