This is probably one of the single best deals ever. Along with the release of Left 4 Dead, Valve is putting together a package deal that contains every game they have released including the new zombie shooter. The best part? The whole thing is only $99! According to Valve this pack will save you $134.81.

Hit the jump for the complete list of included games.

• Counter-Strike
• Counter-Strike Condition Zero
• Counter-Strike Source
• Day of Defeat
• Day of Defeat Source
• Deathmatch Classic
• Half-Life
• Half-Life 2
• Half-Life 2: Episode 1
• Half-Life 2: Episode 2
• Half-Life 2: Lost Coast
• Half-Life Deathmatch Source
• Half-Life Blue Shift
• Half-Life Opposing Source
• Left 4 Dead
• Peggle EXtreme
• Portal
• Ricochet
• Team Fortress 2
• Team Fortress Classic

So, if you plan on buying Left 4 Dead, why not go ahead and get everything else Valve has released for $50. Even if you already have a few of these titles, this is still a great deal.