World of Goo is one of those rare games whose concept is as simple as it is ingenious. The aim is to transport a pile of slime balls, the eponymous goo balls, from tube A to tube B using bridges and crossbars. The trick is that the little Goos are also our building material. If we use too many to stabilize the constantly wobbling construct, we won't have enough to complete the level. If, on the other hand, we are too sparing, our construction will collapse if the load is too high. It is therefore important to build cleverly and with foresight so that the cute, squeaky, googly-eyed balls do not fall into the countless chasms.