I replayed HL2 last year using this: http://store.steampowered.com/app/290930/
(it has improved lighting, but iirc cinematic mod is much more advanced eye-candy wise)

I also saw this one, and another one called "remastered" or something but the review seem bad on theese mods. Addind nothing particular and especialy no new high res textures people said.

The point of attraction for the mod he posted is that it fixes all the bugs that Valve added to the game when they updated the engine to the Orange box/EP2 version. Many people were pissed off that 1) they never tested that shit. And 2) never bothered to fix any of it.

And it's also an officially supported mod, made with the active contribution of Valve.

It adds new "high res" lighting.