Black Mesa, a fan conversion of Half-Life using the Source engine's bells and whistles, will be all yours in as little as two weeks. And it only took eight years.
The Black Mesa website updated over the weekend with a countdown timer indicating September 14.
Confirming the date as the re-make's launch, a forum post said the team decided to release as much of the project as is complete right now rather than make fans wait any longer.
The content releasing on September 14 will take players right up to Lambda Core level, but not beyond and into Xen. That's about eight hours worth of play already, and the Xen segment is apparently taking a little longer because it's being expanded.
Black Mesa was announced in late 2004, but that it's approaching release at all is pretty special; it's made entirely by a shifting team of fans in their free time, and has gone through several engine changes as Valve updated its Source tech. Plus, unlike Valve's own Half-life: Source, it's an actual remake, not a port - with all new models, maps, textures, voice acting and soundtrack.
On that last note, you can grab the project's soundtrack on a pay-what-you-want scheme here.
Black Mesa doesn't require a copy of Half-life, but you will need to have a Source engine game installed. Since everyone on Steam seems to have Portal 2 by now, you're probably set.