Tumblr, Memebase, StumbleUpon, deviantART (unless you're not artsy, heh .w.; ), myYearbook (only if you're honestly that bored), WeHeartIt, Clever Bot (he's grown a little more...PG over the years :'D) and a ton of others.
...Don't go on 4chan, though. You have no idea how much I stress this. NEVER. GO. ON4CHAN. ._________.