Mac software similar to SubEthaEdit?

Hi, I’m trying to find something that will enable me to figure on any document online which has a friend collectively on one document, the changes being produced shown instantly.

Basically Subethaedit, although other software package.

Here you’ll find list of Collaborative real-time writers:http://mozymac.com/forums/f16/list-collaborative-real-time-editors-mac-os-x-4967/#post10164.