How long can a writer go w/out checking email?

For me, not very long. Probably 10 hours max, and I’d have to be sleeping for most of it. I’m headed to Denver tomorrow for a biz trip and won’t be able to check email until around 10pm. I think I’m having an anxiety attack. It’s especially tough if you’re juggling clients – the ones who want you to be available 24/7…or at least 9 to 5. What’s the longest you’ve ever gone w/out email and how did you feel?