If, like me, you spent your formative years gunning down Vortigaunts, running from hordes of headcrab zombies, and cowering in terror from sound-sensitive tentacles the size of an apartment building while making your way through Valve's genre-defining Half-Life, you'll be delighted to know that the long-awaited Black Mesa is finally available to download. Black Mesa, of course, is a ground-up rewrite of Half-Life using Valve's Source Engine, and it's a game that seemed like it might never arrive — but the team behind it has made good on the countdown that started a few weeks ago.

While we haven't given the game a thorough play-through yet, it's the kind of game that is a no-brainer to try. It's a long-awaited and highly anticipated mod, a great deal of work has gone into the project over the years, and Half-Life is overdue for a fresh visual polish. For those interested, it's a free, Windows-only download that goes through the first 80 percent or so of the game — the levels on alien world Xen aren't complete yet and will be added at a later date. The Black Mesa servers are getting hammered right now, so best of luck in downloading.