I love collecting movies trailers especially those upcoming movies that I’m looking forward to watch. Unfortunately there is no download button on Apple Movie Trailers website. A site called Trailer Freaks, however, has the trailers with their direct links listed on the page. So you can simply right click on the link and save the movie file to your computer.
Have fun! (if you can’t find your favorite upcoming movie trailer on TrailerFreaks, you can try downloading HD movie trailers from Dave’s Trailer)