Im sure its already been mentioned but I really enjoyed John Carpenter's remake of "The Thing." High suspense and great sort of moist, organic looking special effects. The alien organism almost seemed to have a compelling biological basis in reality.

Can't say I've ever heard special effects described as moist and organic looking. I'll never look at them the same again.

well i love horror movies especially horrors that can make you laugh although i don't think they end up being that scary but a couple movies that i think are good:

Drag me to hell, District 9, Wishmaster, Ginger snaps-not very well known but absolutely fantastic, Ils (French movie), Battle royale (Japanese movie), Shaun of the dead- obviously one of the best horror/comedies, Fido- also not well known but it has billy connoly as a zombie pet! Zombieland-hysterical, and its not exactly a horror movie but Oldboy (Korean movie i think) it's pretty twisted

thats all i can think of for now

Cujo
Wishmaster 1,2,3,4 was ok if you like gore
Scream 1,2,3,4 great movies
Kill joy 1,2,3,4 funny has hell all are great

Of course there are a lot of good horror films before 2000 but post 2000 I can think of Pan's Labyrinth, Let the right one in and, I agree, The Descent. Was The Others post-2000?