Sometimes, trailers are just mind blowing, in many cases they are far better than the final product.
Particularly in recent years when they are cut so brilliantly.
My favorite trailers are:
Man of Steel (the third trailer is probably my favorite trailer ever)
Avengers Infinity War (the first teaser gives me goosebumps)
Mortal Kombat (i still listen to that kick ass techno score)
Inception (the folding city...like WTF? was my reaction)
Iron Man (the first one with the Audioslave song)
Aliens (the shot of the mech suit melted my brain as a young boy)
Transformers: Revenge of the Fallen (for obvious reasons)