Freaking News ran a Star Wars movie poster Photoshop contest earlier this year. The results are in and some of these are pretty unusual. One of the most distinctive is a sort of mashup between Darth Vader and The Dark Knight. For some reason, it kind of works. Some of the other entries are a bit strange, but they are all kind of humorous.
There are a few which feature Chewbacca which are pretty goofy, but the Panda Wars and Empire of the Sun posters are also awesome. If you’re adept with Photoshop or have some funny ideas, Freaking News runs these sort of contests all of the time.