Teaching literary reading through collaborative annotation

Would others be interested in a discussion of collaborative reading / annotation tools and pedagogy? Whether the goal is simply prompting reflective and engaged reading practices in general education students or developing a collaborative critical edition with graduate students, the idea of social reading is attractive. I would be interested in discussing and sharing ideas.  What tools (Wiki, Commentpress, ebook…) have folks used with success? What parameters or frameworks facilitate active learning and the creation of a useful “product?”  Is there a workable way to integrate mobile devices for in-class participation?