I'm kinda shocked by the comments referring to Slack. Wave was very different from any other chat platform. You could edit everything, add different media elements to the document/channel and keep commenting everywhere on everything. Slack to me is really just another chat software. I see very little difference between it, campfire or Hipchat and honestly for the life of me don't understand why everyone transitioned from Campfire to Hipchat and now to Slack.