As if the next few months weren't going to be distracting enough for gamers, Valve have gone and made its first-person puzzler Portal available to all gratis on Steam until Tuesday the 20th of September.
Portal, which launched back in 2007 alongside Team Fortress 2 and Half Life 2: Episode 2, went on to be a surprise runaway success, scoring 95 out of 100 on Metacritic across Xbox 360, PlayStation 3 and PC and leading to the equally well-received Portal 2, which picked up the Best PC Game, Best Xbox 360 game and Best PlayStation 3 game at the 2010 E3 awards ceremony.
Trapped underground in the abandoned laboratories of the sinister Aperture Science, players must navigate a selection of testing chambers using a pair of reality-bending connecting portals. Standing between the player and freedom are roomfulls of poisonous goop, chatty machine gun turrets and a sociopathic robot invigilator with a fondness for neurotoxin.
Would-be test subjects eager to further the cause of science need only download a copy of Steam and search for Portal to get in on the action. Missed out on Portal the first time around? Check out the teaser below for a look at what all the fuss is about.
Portal teaser trailer