For all its glory back in 2005, it can be a little disillusioning to fire up the original Half-Life 2 these days - it looks that much flatter and dimmer than the worlds we're used to from more recent iterations of Source engine. No HDR or colour correction, and NPCs with pudding-like faces. The one-time Future Of Games doesn't look so futuristic anymore, in other words. So, one man has sprinkled modern fairy dust over the old dear - porting the entirety of Half-Life 2 to the significantly shinier Orange Box version of Source.
It's fairly unclear what side of copyright law this lands on, as while the mod (for lack of a better word) won't run without both HL2 and HL2: Episode 2, its 1.44Gb of recompiled maps'n'that (done, he claims, by manually comparing decompiled PC maps to a long playthrough of the already-upgraded 360 version) does seem to contain a fatted clutch of Valve assets. Whether they're bothered about that is another matter - they're surely aware of it by now, after all.
But it does also mean that it's currently fairly tricky to get hold of the mod - it's all strewn over Rapidshare, Megaupload and the like. Have a browse of the thread on the Steam forums and see if you can find a goodie.
Alternatively, wait until it spreads a bit, and enjoy this side-by-side comparison video and the update and original HL2 in the meantime:
That has at least 37 more beauty-ohms, by my count. Perhaps even 38. Hopefully Valve won't stamp on it, as it's good stuff, and it seems pretty unlikely at this stage that they're ever going to do the same thing for HL2 PC officially.
Oh, and it's got Achievements in too. Whoopie.