Once upon a time, there was the Experimental Gameplay Project. Created by students at Carnegie Mellon University, the first game created for the project was a simple tower creation sandbox game dubbed Tower of Goo. In this experimental game, you used goo balls that could attach to each other with elastic strands to build a tower. Pretty simple. Upon taking a look at the game he had just prototyped, the creator, Kyle Gabler, decided that this game would be the basis for a larger experience. Working together with a coworker from EA named Ron Carmel, they crafted an indie darling that merges excellent physics gameplay and clever puzzles into a professionally-made game that surpasses many games made by major development studios. World of Goo is simply incredible.