I would either do as already suggested, pop a movie (mainstream) sponsor on it and plenty of google adwords or leave a message "This Domain Name Is For Sale" and name a price you would be happy with. I do not agree that the movie sponsors will be too bothered and make an offer unless they feel it could be for sale at a reasonable price.
Latest release in the UK "Iron Man" take a look for yourself and you will see that Marvel have IronManMovie.com. Personally SB I would try and sniff out the domain that the movie producers already have lined up
