EtherPad : Etherpad is an Open Source online editor providing collaborative editing in really real-time powered by Node.js
MUTE : Web-based text editing tool that allows to edit documents collaboratively in real-time. It implements a CRDT-based consistency maintenance algorithm f...
RegPack : RegPack is a packer intended for use on minified Javascript code.
It is mostly suited to small size constraints (1kb, up to 4kb).