Beer Fest and Evolution are great. Also liked the Ballad of Ricky Bobby! That one will be a classic one day.
Just watched Equilibrium with Christian Bale and Taye Diggs earlier...nice commentary on what makes us human and the action scenes are good.
Purely as a social commentary note, try Idiocracy.
What about Even Hand (great cop movie) and Don't be a menace to society while drinking your juice in the hood?
If you have not seen "Hard Candy" with Ellen Page you must watch it immediately. Got to got to got to now.
It is trippy and I guarantee you will be amazed at the end.