I usually have only 2-3 tabs open at the time.
And they're in general all from the same site.
But when I start my browser I usually check these sites:
Exilian (new replies, unread posts and who's online list are my usual suspects)
Taleworlds (started visiting it again lately, always in combination with Exilian)
I just check Facebook or Trading subforum on a Croatian Warhammer site, to see if there are any new sales/auctions or notifications. I usually don't read stuff posted on Facebook.
Tumblr (once a day)
AskMen (I usually read an article or two, but I haven't done that in a while)
Right now:
Exilian - this thread
Warhammer forum - trading section
Taleworlds - updated threads