Minority Report - Looks like it was shot on chrome. Great post processing on it.
Avatar - Never felt that way after leaving a cinema before.
Blade Runner - The cinematography is second to none.
Oldboy - An absolute joy to watch.
O Brother, Where Art Thou? - The dust bowl look gives this movie so much more atmosphere.
Honourable mentions - Brick, Kiss Kiss, Bang Bang, Memento, Fight Club, Se7en, Brazil and Sin City.