Everybody knows how to ride a bike, right? But not everybody unlearns how to ride a bike. But Destin Sandlin did just that [1] (link via Jason Kottke [2] and no, it did not involve injury or a rare disease—he did this intentionally). He also untaught his six-year old son, who proved more adaptable because he was younger.
So, how do you unlearn riding a bike? Well, first off, you get a bicycle that steers backwards …
[1] https://www.youtube.com/watch?v=MFzDaBzBlL0
[2] http://kottke.org/15/04/the-backwards-bike-will-break-your-brain