All this talk about multitasking...it's time to talk about its corollary - deep focus, being in the flow, in the zone. I find it a wonderful experience. And goodness knows there are plenty of things keeping us from being able to focus for periods of time.
Intel now has no email Fridays, when employees are encouraged not to use email for internal communications. I love that idea. I've taken to checking it far less often during the day, other wise it can easily turn into the tail wagging the dog.