World of Goo
Metacritic score (out of 100):
This is a puzzle game where you use balls of goo to create a multitude of structures, including bridges, zeppelins and even "giant tongues." And unlike the inanimate building blocks of "Tetris," these goo balls apparently have feelings and personalities too, as the game's developers claim that several species of goo "come together to ooze through reluctant tales of discovery, love, conspiracy, beauty, electric power, and the third dimension." Sounds trippy!