well, almost all people in the theater really shouted "Behind you!" when Shelob was sneaking behind Frodo ready for attack. Actually, I watched ROTK on its second screening here just to survey the audiences' reaction on every scene, and it really delighted me when they, especially the newbies, react to scenes that they are suppose to react which I think makes a particular scene effective - they were all shaky when Gollum "tried" to seize the ring on top of the Stairs..laughed when Pippin & Merry where left a little behind while running with the armies in the Black Gate..clapped at Legolas' ride with the mumakil..and so much more. I really felt I was like Peter Jackson on a press preview at that time.
