Valve's gone and released a new collection of all its titles on Steam, in what it's calling the Valve Complete Collection.
This means you get all the Half-Life titles - from the first game all the way through to Half-Life 2: Episode Two - Portal, Team Fortress 1 & 2, Day of Defeat, Counter-Strike and importantly the upcoming Left 4 Dead.
Best of all is that all this will only set you back $99. Sure most PC gamers will have already picked up a lot of what's included, but for those who haven't this appears to be a fantastic bargain.
You'll find more info over on steampowered.com