Valve has updated the PC version of its first-person puzzle classic Portal with an enigmatic patch which has set fans on a trail of code-cracking and puzzle-solving.
The patch notes for the update simply, but enigmatically, read: "Changed radio transmission frequency to comply with federal and state spectrum management regulations."
What it didn't mention was a new Steam achievement for the game called Transmission Received. Completing the achievement involves carrying a radio around the game and receiving broadcast interference noises in certain places.
Analysing these sound files, Portal fans have begun unravelling a thread of puzzles and challenges apparently set for them by the Seattle developer. As Steam user relaxeder summarised in the lengthy forum thread:
"Smart people yank .wav files out of game content folders and run them through steganography programs. Produces 26 weird cryptic image files in a numbered sequence.
"Some dude runs the number string through an md5 hash translator and gets a landline number. Internet traces it to Kirkland, WA (near Valve HQ).
"People find out it's not a phone/fax line but a data line hosting a BBS and telnet it. Use a clue from one of the files to figure out the BBS user/password login info. End up with a bunch of weird ASCII artwork.
"We're trying to figure out WTF it means."
Aren't we all, but we wouldn't be surprised if the trail led to an announcement of some sort related to Portal or the loosely-connected Half-Life universe. More as it breaks.