What would you say would be the best way to do this:

We would like to create a section on our activist community FB page and website in order to share with everyone images and files ready for printing panflets, brochures, t-shirts, stickers, etc. Let's say we have some cool slogans for t-shirts, so we would like to show them on a gallery, and offer for download the original design files needed for a print shop to create the t-shirts. And the same thing for all other kinds of media. We want to enable anyone to be able to just download the files for free, and easily create printed materials with them. But besides offering this hybrid between picture gallery and downloads manager, we would also like to make it very easy for anyone to upload and share their own files with the community, to make it a true collaboration initiative, be it that they get posted automatically, or that we first review and approve all uploads.

Cafepress or Spreadshirt let you upload your design and sell your own merchandise. We need something similar, but where people can then download working files for making quality printings and materials.

What apps, tools, services or methods are out there with which you think this could be best done?? We have some ideas, but we would like to hear some more!!