Cloud9 Collaboration mode is also open source: https://github.com/c9/c9.ide.collab (Same code that's used on http://c9.io which can be used for free). Has chat and ability to work with multiple files out of the box.
Tried yesterday with my colleague. Actually, it only supports one file per session (see TODO in the README), IMHO this limit doesn't make it usable for a real pairing session, especially when you need to work on several files in a project.
Maybe not terribly useful for real world programming (while there is a one file limit), but for interview coding sessions it seems brilliant to me. Great work!
I realize that this was developed in-house by Pusher, but what I'd really like to see is floobits-atom reach maturity since their service is already editor-agnostic.
An "old idea", but executed brilliantly. I absolutely love this, and will be watching the development closely.
I've always been a fan of 'pair programming' even remotely using Skype for example... but that's not that great (you can only watch, or one person can only work at any single time) but this is actually designed for real pair programming over the internet. Love it!
I've started a project doing pair programming livestream sessions. We're using floobits integration with sublime as editing (multiple) local files is ideal.
If this reaches that level I'd love to try it out.
It's been a little while since I thought about it, and I may not be considering exactly the same use cases, but I'm pretty sure I'd do something vaguely like this:
Initiator of session holds authoritative file.
Guest receives full file upon connection.
Diffs are taken on each change (onkeypress event)
( for simple key mapping invariance (♥λ) ).
Shoot the diffs over the wire, and apply the updates.
From what I understand, Atom has a pretty big user base and it's getting larger. Now that they've squashed a lot of the bugs that plagued the early versions, it seems to be taking off.
Note: I've been using it for over a year, so I may have a biased view as a member of the community.