World of Goo is a physics-based puzzle game created and published by independent game developer 2D Boy for WiiWare, Mac OS X, Windows, and Linux. Based on Keller Gabler's concept game Tower of Goo, Sticky World's main gameplay consists of using sticky balls called "Goo" to build architectural frameworks. In addition to several single-player levels, the game offers a competitive online mode that allows players around the world to challenge Goo height records. At the 2008 Independent Games Festival of America, Sticky Worlds won the Innovative Design Award and the Technical Excellence Award, and was nominated for the Seumas McNally Award.

The basic goal of each level is to collect a certain number of Sticky Bean Bags to a water pipe leading out of the level. Players will have to find ways to use the sticky beanbags to construct structures such as bridges and towers while overcoming gravity and unfavorable terrain such as chasms, peaks, cliffs, and spikes in order to ultimately build the structure up to the mouth of the water pipe in order to allow in the sticky beanbags that were not used to build the structure. If the player manages to collect enough sticky beanbags they pass the level. If more than the standard amount of Sticky Bean Packs are collected, the excess can be used in online mode