HL2: Episode One released

Half-Life 2: Episode One is available now through Valve's digital distribution system Steam.

Released at 6pm this evening UK time, the game's a 4-6 hour episode that you can purchase and play without owning Half-Life 2 - although it picks up from the end of that most celebrated of PC shooters. Valve plans to release two more games in this series of episodes.

Reviewed on the site today and heavily trailed on Eurogamer TV, it's probably the most highly anticipated event in digital distribution since, well, since Half-Life 2 itself.

Those of you who already have it pre-loaded and pre-purchased will find the game files decrypt when you next load Steam, while those pre-loaded can purchase at their leisure for $19.95, or you can start from scratch by buying and downloading - although you might find it takes a while given the number of people likely to want to get hold of it now it's out.

Finally, it's worth pointing out that if you can't be bothered with all this Steam nonsense and you'd rather have one of those boxed games like in the old days, you can do that from tomorrow - with EA distributing the game through UK retail for around £15.

And with that, we'll shut up about Half-Life 2: Episode One. Although obviously we'd love to hear what you make of it.