If you're ever in the woods and a big ass tree falls on you, run to the side about 10 feet. Don't run down the length of where the tree is falling, because 10 feet is a lot shorter than the height of the tree.
Apparently you should think about this and get your mind prepared before it happens though; from all the movies I've seen apparently too many dumb people want to run the length of the tree/long piece of crashing spaceship.
I watched it twice though. The special effects are better than anything I've ever seen.