Gobby/Sobby is an open source client/server for collaborative edition of plain text file (source code).
My question is 4-fold :
Thanks Jerome
Yes
Mostly, you encounter issues running Windows clients (random crashes). Find a version that works and stick to it.
I recently started using it with the team I manage. It has definitely increased my productivity when reviewing code, implementation collaboration, and answering general questions. It's great for those "hey, can you take a quick look a this?" questions.
We have only used development release 0.4.93.