Hypothes.is is a tool for collaboratively annotating almost any site or pdf on the web.  It is great for engaging in open conversations about an article or website where participants can highlight particular pieces of text and make comments, while others respond. This kind of “social reading” can be very powerful.  Go to the website to create an account and download the extension for your google chrome browser.  Biologists have led the way in using hypothes.is for open group scientist annotation of research articles. Check out the Bioscience uses and events.  This tools also allows us to give each other specific feedback on our domain posts.