No, this is not a figment of your imagination, but Figment: Write yourself in. Figment is a site where student writers can share reading and writing in a private online group. The site boasts about writing prompts, virtual writer's workshop, and authoring programming.
Check out this video for educators!
You'll be using 21st century tools when you allow your students the creativity to use this site, collaborate with others around the world, post assignments and monitor progress, and publish writing pieces! Best part as always is it's free! Check out Figment today and let me know how it works for you!