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Just when you thought nothing in gaming could be done quietly, it seems that Valve has done away with the fanfares and the fireworks, releasing beta versions of Half-Life for both Linux and Mac OSX without actually telling anyone.
Visitors to the Half-Life page on Steam are faced with a seemingly Windows-only experience, but gamers at both Phoronix and Cult of Mac report that the original FPS is available for both alternate operating systems and, indeed, works rather well.
While not officially labelled as one, it's best to think of the Half-Life release - at this stage - as a beta release, which would explain both the lack of announcement and the page not being updated. If you're ready to jump back into one of the most influential games of all time, then we can think of a worse way to spend US$9.99. Just make sure you send us a postcard.