Your task: use Blockstack to write a toy version of Piazza. It should support multiple users, posts, replies to posts, and private posts to course staff. The private posts (and replies) should be encrypted so that only the course staff and relevant student can read them.
Due: Tuesday September 25th at the start of class. E-Mail your HTML and JavaScript to rtm@mit.edu.
If you are looking for challenges, try anonymous posts, support for large numbers of interacting users (perhaps a system more like Reddit or Hacker News), voting on posts, user karma, and spam post detection.
Here is a discussion about building forums on Blockstack.