Etherpad is basically a super simple Google Docs. That's probably a shitty way to describe it but whatever.
I want to do some experiments with it, and it can be useful for collaboration or even just brief usage to share things. I do not promise not to look at what it is used for, or to keep things up, but if you want to use it, I have an instance at https://etherpad.tangentfox.com now.