Valve has announced that Perpetual Testing Initiative, a free DLC (downloadable content) released for Portal 2 three day ago, has already resulted in the creation and publishing of over 35,000 user-created maps, collectively consumed via more than 1.3 million downloads. To celebrate the launch, Steam is holding a Weekend Workshop Sale offering Portal 2 for 66% off, Elder Scrolls V: Skyrim for 33% off, and many of this year's Team Fortress 2 Workshop Items available for 50% off their regular price.
The Perpetual Testing Initiative allows players to easily create, share, and play Portal 2 puzzles. The Initiative comes with a simplified Puzzle Maker that allows that creation of mind-bending puzzles without ever leaving the game. The Puzzle Maker directly publishes maps to the Steam Workshop where users may browse, vote on, and select to play them. Selected puzzles are automatically downloaded and installed inside Portal 2.