The movie Blade Runner is a pretty substantial departure from the Phillip Dick book "Do Robots Dream of Electric Sheep" on which it was based. Even so, and perhaps uniquely in literary history, Dick seems to have absolutely loved the movie. It kept the right elements of the book - ie, what makes us human -- and shed the silly, trippy stuff.
I don't remember it being a huge box office success. Probably too dark, even with the last minute change of ending (the happy notion that Rachael had no programmed termination date was added to give audiences a more upbeat ending.) But the movie certainly had a huge effect on the look and feel of sci-fi. After the Matrix and the Terminator, we are used to future dystopias, but in the 1970's most popular sci-fi had cities that were as bright and shiny as a new penny. I remember seeing it the first time, and Blade Runner was arresting, a whole new category of sci-fi noir. I still love the movie, and it wears pretty well, but nowadays fan argue endlessly of the merits of the original release vs. the directors cut. The latter purges the Harrison Ford narration and happy ending that were tacked on to make the movie more audience friendly. I personally like the narration-- it feels consistent with the noir genre -- though the faux happy ending is lame.
If George Lucas needs any more money, here is my movie idea for him: Make a movie about Han Solo and Chewbacca in their early years. How did a Wookie prince become a smuggler? How did he meet Han? How did Han win the Millennium Falcon from Lando? In my imagination, the movie would be more in the spirit of Raiders of the Lost Ark rather than the most recent star wars movie, putting the emphasis on adventure and action over special effects, Republic politics, and endless light-saber fights. The only real challenge would be casting the young Han Solo part -- who would be willing to try to replace Harrison Ford?
Does anyone doubt that this would make a fortune, particularly if you teamed Lucas with someone to do the writing? The series would easily lend itself to a serial format, with multiple episodes, though in that format it might make a better TV show than movie.
PS- I got started thinking about this because I saw Star Wars III again this weekend. As an update to my review: it did not wear very well. The back third from the (attempted) arrest of Palpatine forward was still engaging, but the front half actually had me squirming in my seat. The dialog still sucks, the initial mission sequence still makes no sense, and the battle with General Grievous is still just one more gratuitous light saber battle and chase scene.