1. TV Tropes. Good god, TV tropes. this website has distracted me more than any website, ever.
It's a soul sucking abyss.
2. Online Games. WoW, Farmville, Cafeworld, even Runescape gets an honorable (or is it horrible) mention for things to avoid even thinking about while trying to write or do homework.
3. Facebook, your just one Meme away from ruining your productive day.
4. Hyperbole and A half. Allie, the MS Paint wonder, has some of the funniest stuff I've ever seen, but it sucks my time second only to TV Tropes.
5. Blogs, in general. Yes, the very thing you reading. What exactly are you supposed to be doing right now? Hmm? Working? Homework? Nope, you're on my blog endangering your job or future.
6. Last but not least, Youtube. Skatingboarding Cat? Awesome. Sneezing baby panda? Super. Renditions of Going Through the Motions? Even better! put this all together and you have a good five hours wasted.
GO BACK TO WORK!