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.
4chan - 4chan is a simple image-based bulletin board where anyone can post comments and share images.
SaidIt.net - Saidit.net - say your truth.
Folkd - folkd.com - Social Bookmarking - Save your bookmarks and links online and search what your friends like.
Tildes - A non-profit community site driven by its users' interests
Raddle - A web-based forum where users submit links, pictures, posts, etc.