I think I’ve seen this done, but is there a way to create a public collection of your own files along with other files from other users?
There sure is, go to an item on any of the marketplaces, scroll down and in the sidebar is a place for you to bookmark the item to a collection. Choose “Create New Collection” and tick the box that says Publicly Viewable?
This will make your collection, which you can find by going to http://photodune.net/user/stemlund/bookmarks.
You can then go to other items and bookmark them to the same collection!