Etherpad is the latest very, very easy way to collaborate in real time. You just paste a bunch of text in a window and, without even having to register for the service, send others the url and everybody can edit it in real time. It also has a chat option.
You can go back to the url address at any time to make further, adjustments, too.
Because of these features, I’m adding the site to both The Best Online Tools For Real-Time Collaboration and The Best Online Tools For Collaboration — NOT In Real Time.
Thanks to the Read/Write Web blog for the tip. Their post shares more information about the service and is worth a look.