Just. Stop. Clicking!
Reading has always been my favorite activity to do. The internet has simply increased the amount of stuff I get to read (often to the detriment of things like updating the blog). One of my problem sites is Wikipedia simply because I can go for hours clicking random links from the inside of articles that I looked up to get a “quick” answer. A new one for me is TVTropes.org, which has sucked a ton of time from me today based on an off-hand link to the Xanatos Gambit. That led to all kinds of other Xanatos things and reading about where they appear in popular media. Unfortunately, I can’t stop clicking. 
edit: Fork, I just spent 20 minutes reading about That One Boss and The Computer is a Cheating Bastard. I was trying to close the window.