Eastern Standard Tribe by Cory Doctorow

Doctorow breaks the Internet. Into time zones. Since people seem to prioritize who they chat with, he hypothecates people living according to preferred time zones where they can chat with their friends.

Of course, one of the really cool things about the 'net is that people can share ideas half-way around the globe (say from Singapore to the United States ;). So part of this is the lol-worthy idea "wouldn't it be funny if the Internet was self-invalidating". The bad thing is that does not make a self-validating book.

He propped several pillows up on his headboard and fired up his comm. Immediately, it began to buzz and hum andchatter and blink, throwing up alerts about urgent messages, pages and calls pending. The lightness he'd felt fled him, and he began the rotten business of triaging his in-box.

-- Chapter 16