Gnoosic - Even if you don't know what you are looking for - gnod will find it.
Food 52 - Social network for foodies.
Musicroamer - A visual Pandora for discovering new music
munchlab - Get recipes based on ingredients you have at home
TasteDive - TasteDive recommends similar music (musicians, bands), movies, TV shows, books, authors and games, based on what you like.
Plant Jammer - Reduce food waste and save money - cook with what you got!