Brian Tracy (famous get what you want type guy) talks about only ever handling a piece of paper once. Do something with it once only. The same should apply to email.
I always look an email and think, if I did nothing with this, would it matter. If the answer is no (it would not matter). I delete it.
And short, curt answers are often better.
Don't forget about not checking email 1000 times a day either, why not just check it once an hour or something like that.