Have you ever heard of World of Goo? That hit indie game by developer 2D Boy? It'll be heading to Android some time soon and the game is already in the final stages of testing. For those who don't know - the World of Goo is a physics based puzzle construction game.
The main objective of the game is to get a requisite number of goo balls to a pipe representing the exit. In order to do so, the player must use the goo balls to construct bridges, towers, and other structures to overcome gravity and various terrain difficulties such as chasms, hills, spikes, or cliffs. There are several types of goo balls in the game, each of which has unique properties.
The player must exploit combinations of these goo balls in order to complete each level. Extra goos recovered in the pipe are pumped through to the World of Goo Corporation, a sandbox area where the objective is to compete with other players worldwide by building the tallest tower possible.
Ok, that was taken from Wikipedia, but I think you get the gist of the game. Here's how the game looks and plays like: