Available today are Relic Entertainment's Company of Heroes, Iron Lore's Titan Quest and Titan Quest: Immortal Throne, and Pandemic Studios' Full Spectrum Warrior and Full Spectrum Warrior: Ten Hammers. Each has a 10% discount from its standard price until July 24.

THQ plans to make available several additional games in the near future. On the way are GSC Game World's S.T.A.L.K.E.R.: Shadow of Chernobyl, Relic Entertainment's Warhammer 40,000: Dawn of War Gold Edition, Warhammer 40,000: Dawn of War Platinum Edition, and Warhammer 40,000: Dawn of War: Dark Crusade.

"In the past couple years, THQ has established itself as one of today's premier PC publishers," said Valve co-founder Gabe Newell. "It's great to finally be working together with THQ and its studio system and offer this award-winning line up to Steam's growing audience, which represents over 13 millions accounts."