What about STALKER: Shadow of Chernobyl?
Seriously, SoC is one of the few games I've ever played that has drawn me right in, with the low-contrast, post apocalyptic scenery and great ambiency as well as the long, duck/shoot/hide firefights...
Good taste. I bought the game in 2007 but didn't play till 2010 when I noticed some heavy texture mods were available. I dare anyone to dawn a set of headphones, turn out the lights and play 'Stalker SOC' or better yet 'Call Of Pripyat' and say this game didn't scare the s h i t out of you some point. It's dreadful, treacherous and unforgiving. The whole atmosphere or vibe is DARK. Pure PC game no porting. Console noobs couldn't handle it anyway haha......
EDIT: When I saw this 'clearsky' atmosphere vid had to buty the game. Love all the DX10 effects especially the sun and raindrop effects.
BTW: FO3 with heavy texture mods is a beautiful game.