I have been thinking about the logic of a long-form trailer for my project next year. The trailer is a fascinating storytelling format, it is a tale that hints at a much larger narrative while delivering all the emotive character of the whole. There are some nice expectations and genre 'standards' around the trailer format, in much the same way as for features. This along with clever use of sound, voice-over narrative and clever editing create all manner of cool results.
Here are some fun trailer recuts, using these methods to deliver some very cool changes to the likes of Sleepless in Seatle, Mary Poppins and a Dark Knight/Toy Story thing:
There is a relationship to advertising as well, a trailer is really a TVC for a film or tv series. I liked the Cadbury Favourites TVC just now :-)