Valve games now available via GameStop's Impulse

Newsbrief: GameStop has announced that a number of games from publishing giant Valve are now available to purchase via the Impulse digital distribution service. Portal 2, Left 4 Dead, Half-Life and The Orange Box can be bought via GameStop's Impulse, although the games still need to be registered using Valve's Steam client. This is the first time Valve's games have been available to purchase via a digital source other than its own Steam service or via retail.