If you've got some holes to fill in your Half-Life collection, or if you've somehow missed the series entirely -- perhaps the result of an interdimensional anomaly -- this weekend is your chance to catch up. This weekend on Steam, absolutely every Half-Life and Half-Life 2 product is available at 66% off. For instance, you can snag the Half-Life Complete Pack, which includes both Half-Life games, every Half-Life expansion, both Half Life 2 episodes, Team Fortress Classic and Half-Life 2: Deathmatch for only $16.99. If you'd rather pick up only a few individual pieces, most of them can be had for only a few dollars.

Beyond the Half-Life games, the Valve Complete Pack – usually $99.99 – has been knocked down to $89.99. If you've missed out on Valve's brand of goodness over the last decade, this pack will bring you up to speed. Half-Life, Team Fortress 2, Portal, Left 4 Dead: You name it, it's in there. Use that $10 for a bag of delicious Arby's, and you've got a solid weekend of gaming bliss.

This article was originally published on Joystiq.

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