Let's Chat – open source, self-hosted chat for small teams
sdelements.github.io
sdelements.github.io
That's why products like Slack, HipChat, Campfire, etc exist.
Having a web irc client that provided a common backlog and search for all users, instead of requiring things like znc to make that usable, would be great. The private part is fraught though.
A really high quality web (maybe even HTML5 client-side only even?) XMPP client would be a welcome thing. This, not so much.
Unlike the people who can't figure out why this is better than IRC, I find a ton of value in your project. After leaving Campfire, moving to Kato, and then settling with Slack, I am really unhappy with the Slack mobile experience.