Quote: Originally Posted by Neowin.net
In celebrating the launch of Steam for Mac today, Valve Software has put out an enticing promotional campaign differing from their usual free weekends for content pack updates to their other games, such as Team Fortress 2 and Left 4 Dead. This time, they will offer Portal for free, for everyone to keep forever, as long as they respond by May 24. Both Windows and Mac OS X gamers can once again play the much loved puzzle shooter of 2007's The Orange Box that has won nearly 70 Game of the Year awards.
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Get Portal for free here
! (Requires Steam to be installed) NOTE
(5/12/2010): Currently the servers are being hammered, so those who have not so great internet connections may want to wait until tomorrow or the day after to download this game. NOTE
(5/13/2010): Servers are starting to catch up and letting download speeds stay stable. Please keep in mind that the game WILL require Steam to play, if you remove Steam after installing Portal, you wont be able to play Portal.