I am, of course, a vi user (well, Vim actually).
A long time ago I had a nice idea, which unfortunately wasn’t very practical so I didn’t use it for long: I remaped my Tab key to work as Esc, so I could more easily switch modes. I say it wasn’t very practical because getting used to it meant that I would have the wrong muscle memory whenever I was in front of another computer (this was also the reason why I used the Dvorak layout for only a few months).
I couldn’t help but smile today when I found out that the computer terminal where Bill Joy developed the original vi had the Esc key where the Tab key is nowadays. 
