There's lot to do... I spend like 15 hrs. online almost everyday and always find this new site, that new UBB...
old comics from bt, foul mouthed and cynical games critique, amateur novelists posting some fresh and nice writing somewhere, browse comments about your favourite movies at imdb, 1000 post extreme flamewars about any silly non-event on an obscure forum... Learn about WWII, Age of Sail history, RC planes, politics, virtual communities, game developement...
Heaven for the attention deficit disorder junkie!
Of course there are times when you are just sick of it all, I tend to use those for getting some work done, actually paying attention to the wifey or socializing.
I'm finding as of late that my ecclectic browsing habits have improved my real life conversational skills. My coworkers expect eagerly the coffee break so I tell them what kind of weird stuff I found last night
now go and do some letter fighting:
http://web.okaygo.co.uk/apps/letters/flashcom/