Storybird is a free collaborative story telling tool. This means you can make your own stories using a large number of artworks available on site, invite others to participate in making your story and once created your story can be saved and published, embedded in any website or blog, shared via facebook twitter etc. A nice tool to start the creative juices flowing. Most of the artwork is based on pictures of animated objects though, and some artwork is not at all suitable for Muslim users, so the choices for Muslim users is somewhat limited, but still it can be a good place to create collaborative stories if used responsibly.
(Not created by me)