I think I get it.
Email is 24 hours per day (for better or worse). When you sleep, people are emailing you. When they sleep, you're emailing them. It never stops -- it's a real-time measurement of the changeful order of things, on a vast spectrum from intimacy to global news. When you wake up, words and images will be waiting just for you -- it's as if you hadn't slept at all. That's at least a good chunk of why I dig it so much. Because if I didn't have to sleep, I wouldn't -- I'd be busy all the time, looking around, making connections. My computer identity - my blog, my email inboxes -- are always open for business in some sense. In the world of ideas, this is critical, this open identity -- a large net for all sorts of information, some of it very influential for you (and some not at all.) It's being alive, all the time.
:-) Neat, huh?