Just can't wait to play the Half-Life 2 game? You can pick it up the moment it goes on sale, without leaving your home.

Many fans already have 3.3GB of the game loaded on their systems, thanks to game maker Valve Software's new online distribution method, and are awaiting only a small activation piece to play the full game upon its release (which should be at about the time you read this). None of them will actually pay until they activate the game.

You've been able to download software patches, shareware and some programs and games for some time. Many multigigabyte programs, however, including Microsoft Office, have been considered too large to download even with broadband.

For its 4.5GB game, Valve gets around the issue by offering its downloads in stages. As of early October, roughly 200,000 eager gamers had loaded five parts of Half-Life 2 using Steam, the company's online distribution system.

Online distribution is the wave of the future for many PC apps, says IDC research director Cushing Anderson. He also expects the large tech retailers, such as CompUSA, to eventually offer applications online – either in one chunk or in stages – as broadband continues to proliferate. However, "it will be many years before it becomes the majority of software sales," he says.

There may be a few kinks to iron out along the way. During Steam beta-testing, some fans voiced frustration when the system's bandwidth was overwhelmed. But Steam has been running commercially since March with no trouble, says spokesperson Doug Lombardi. (Two of Valve's Counter-Strike game titles sell via Steam, too.) And much as Microsoft does with its Windows Update, Valve promises to send automatic updates via Steam when the games need patching.

Most game buyers won't be eager enough for new titles to make preload methods such as Valve's the norm anytime soon, says IDC analyst Schelley Olhava. But for those who are, life just got more fun.