The question implies (though, luckily, the answers are not limited) that you use just one text editor. Quite the opposite in fact, I feel if you are just using one tool for the job (always in vim, for example), you are unnecessarily limiting yourself to your tool set.
When all you have is a hammer, and all that jazz.
Edit: I should note that I'm just being whiny this morning. I should go back to playing with code.