The current world population is slightly higher than 8 billion people. If we overestimate and assume that everyone has access to the internet, and assume that everyone goes to Imgflip, and overestimate and assume everyone made up to 100 personal accounts, . . . you're still about an infinite amount away from infinity.
We have some of these, albeit in a different format:
> Monowheel (motor wheel) = motorcycle (which, admittedly, is just a motorized version of a bicycle). The original idea was for a single continuous wheel to encircle and spin around the operator, who remained upright due to gyroscopic effects. However, the monowheel suffered stability issues. As an interesting note: If the engine was engaged and the outer wheel failed to spin, that force could be transferred to the driver, leading to a nauseating (or fun, depending how you look at it) loop-de-loop in your own personal roller coaster.
> Water scooter = jet ski.
> Flying boat / car powered by airplane propeller = hovercraft (air-cushion vehicle / ACV). These amphibious vehicles, while incapable of sustained flight, can be forced airborne for periods, although this "flight" is not exactly stable.
