Valve has fired an investigative drone into the bowels of the Steam Workshop, and it has limped back with the news that over 35,000 Portal 2 maps have been made and published since the launch of its Perpetual Testing Initiative on Tuesday.

That's a whizzy map editor, basically. The service has also seen 1.3 million downloads of these shiny new user-created tests.

Valve's launching a Weekend Workshop Madness party (okay, sale) to celebrate the company's riotous success: Portal 2's been dropped to £5.09 (even though it was still that price from the other day, but never mind), Skyrim's been slashed to £23.44 and Team Fortress 2 workshop items have been trimmed in pri-- OH MY GOD CHEAP HATS.

As usual, the weekend deals will run until Monday in the UK.