At work I have a bunch of tabs open in my browser all the time. Gmail, my admin page for orangefever, NetVibes (RSS reader) and Digg. If I’m at some temporary computer, I may also have Meebo open. Of the 5, all aside from Digg have AJAX refreshes, which means that it periodically refreshes itself.
So when I’m bored, I can quickly skim through my list of tabs to see if anything has changed that I can procrastinate with. I’ve noticed that I’m so accustomed to this behaviour now that when I reach my Digg page, I sometimes wonder why there hasn’t been any new news lately. Obviously, it’s because I haven’t refreshed the page.