Reddit - Reddit gives you the best of the internet in one place. Get a constantly updating feed of breaking news, fun stories, pics, memes, and videos just for you.
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Fluther - Question and answer service based on user profiles and a user score.
Quora - Quora is a place to gain and share knowledge. It's a platform to ask questions and connect with people who contribute unique insights and quality answers.
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Experts123 - Experts123 is a Question and Answer Encyclopedia that provides answers from an Expert community.