Black Mesa has been officially released by the aptly named Black Mesa Modifcation team. The Source Engine upgraded version of Half-Life isn't yet available through Steam, but the developer's website has multiple options for download (it's just a little borked right now). The best part is, the modification is completely free! In order to play Black Mesa Steam will have to installed, as well as as the Source SDK Base 2007 which is also free. Check the video after the break.

Black Mesa offers improved textures, physics, new models, new voice acting, and a new soundtrack. This free game has been built from the ground up, the creators explain on their site that it's not simply a port of all Half-Life maps and models into the Source engine.Everyone should be crackin' crabs with a crowbar in no time.