It’s taken me 3 years to get to this point, but I’m finally able to “turn off” my business e-mail in the evening and on weekends. This has been a very liberating thing for me. I stick the e-mails in a “To Reply” folder and address them first thing in the morning the next business day.
Of course, the downside is when there is a flood of e-mails over a weekend that all get backed up. For some reason this weekend there were a lot of folks on the net checking out Tasks Pro™ and looking for custom WordPress development. I spent about 3-4 hours today just replying to e-mail. That really cuts into the old development time.