I have a habit of typing 'jkjk...' in command mode when I'm thinking, and eventually I got sick of stretching my fingers to escape into command mode so I just used 'jk' as my escape sequence.

    imap jk <Esc>

Of course now in non-vim editors I sometimes have to undo the occasional jk sequence... But my point is that the escape key can be whatever people want it to be.