I don't see a reason why there couldn't be a JavaScript-powered frontend to Vim or Emacs, so sure, I could definitely see myself using one… But, to get this ri

I don't see a reason why there couldn't be a JavaScript-powered frontend to Vim or Emacs, so sure, I could definitely see myself using one… But, to get this right, you want to use one because a) you can't sit and concentrate and b) your device of choice doesn't leave you no other (simple) choice but using something web-based. Fixing one of those premises might be a lot easier than creating a good browser-based IDE.