2D BOY’s acclaimed puzzle game World of Goo is 50% off now on Direct2Drive.

WoG is a puzzle game based around balls of goo appropriately entitled "goo balls." Players connect the balls one-by-one to form intricite, massive and at times unstable structures, all with the goal of reaching each level’s exit point.

The indie game has received plenty of priase, boasting awards including the Interactive Arts & Sciences’ award for "Outstanding Achievement in Game Design."