@melissasage An oulipo-like instance where subsequent posts from the entire pool of users further reduce the number of allowed characters.

Example: User1 makes a post and can use all characters except for e. User 2 makes a post and can use all characters except e and £. User1 posts again, and can use all characters except e, £, and 8.

Once enough posts have been made to exhaust the entire character set, it loops back around to allowing all characters again.