TIME-WASTING TIP OF THE DAY:
While it's true that perusing the Internet can get some folks in trouble at work (though truth be told, your computer guy's probably got better things to do than monitor your Internet usage - trust us), there's one site no one will begrudge you a visit to:
CNN.com. Why? I suppose it's because people have an unyielding appetite for knowledge or at least the security of being "in the know". Folks like to be up on news, so everyone can understand you wanting to read up on it. Certainly an informed employee is a good thing.
So, go ahead, spend as much time as you want there. In fact, just leave it minimized all day and refresh whenever you need to waste more time. Read every little story. Then, every once in a while, drop a cool fact or mention an interesting story as part of your water-cooler conversation. Not only will people appreciate you helping them to keep "in the know", but that will encourage others to slack with you. And as we all learned in grade school, group guilt helps keep everyone out of trouble.
(Note: Other news sites are optional, depending on the political persuasions of your coworkers. Since the point is not to actually "learn", but rather to "not work", go with what the majority of the office likes. Otherwise, you could have to listen to the rantings of some moron while they try to explain to you that your news source is unreliable - and that's worse than doing actual work.)