HowStuffWorks
Is It Any Good?
HowStuffWorks.com provides a wealth of information that's great for researching school projects or just learning something new. That said, the site definitely sells and promotes more than free knowledge (Consumer Guide is a partner), and searches also scour the entire Web, offering sponsored results (aka places to spend money), followed by the site's links.
Overall, the site is an excellent reference, with an emphasis on the nuts and bolts of both everyday (energy drinks, laughter) and not-so-everyday stuff (black holes, lie detectors). If only there was a little less emphasis on selling and more on the fascinating stuff.

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