Portal 2 Perpetual Testing Initiative DLC Released

Create, share, and play Portal 2 puzzles
Valve today announced that Perpetual Testing Initiative, a free DLC (downloadable content) for Portal 2, is now available for PC and Mac. This DLC comes with a simplified puzzle maker that allows that creation of mind-bending puzzles without ever leaving the game.
The puzzle maker can directly publish maps to the Steam Workshop where users can browse, vote on, and select to play them. Selected puzzles will automatically be downloaded and installed inside Portal 2.