I thought this might be of interest to some of the people here.
As I've discussed here before, I'm working on an open-source entertainment project called Trilobyte Studios. It's an effort to create a repository of ideas that anyone can use to create their own stories.
As part of that project, I've created a gallery of resources. While a lot of it is specific to the universes we're trying to develop, there are also a lot of photos and videos to use as establishing shots. They're released under a Creative Commons by-nc-sa license, with a modification: The NC only applies to selling the images/videos "as-is". You can't take a file and sell it as a poster, but you can use it in an advertisement for your company or in your feature film—as long as you abide by the BY and SA portions of the license.
I'm also looking for people who are willing to contribute to the gallery. If you're a photographer, videographer, artist, or draftsman—and you are willing to offer your work for others to use—let me know.