Dr. Strangelove, This is Spinal Tap, Wag the Dog, Heathers, Thank You For Smoking, Clueless, Alfie (the original), American Beauty... not all straight up satires, but have satirical elements... What exactly are you looking for?
I'd add A Mighty Wind, Waiting for Guffman and Best in Show to round out the Christopher Guest/Spinal Tap-esque brilliant recent satires. Airplane was a great satire of '70s disaster movies.
if you want to read a great satire... i'd suggest "A Modest Proposal" by Jonathan Swift... absolute classic of satire it's not very long, and you can read it here... http://www.uoregon.edu/~rbear/modest.html