Lately I've been experimenting with using a collaborative text editor (or plugin such as NppNetNote for Notepad++) for two or more partners to edit source code. I've been met with unexpected success, and the workflow differs from anything I've ever experienced. My findings:
It's fun to fight over code, but also very satisfying to collaborate on it in real time.
Two people can work collaboratively or separately, and be constantly aware of each other's changes.
The comments end up becoming a free-form IM conversation about the code around them.
The medium is enormously less restrictive than trying to work back and forth over IM proper.
It's like pair programming, but with no overhead to switch roles between driver and navigator.
Has anyone tried this before? What were some of the advantages and problems that you encountered? For those that haven't tried it, I strongly encourage you to find a friend (or two, or more!) and make an attempt.
Edit: See Wikipedia for something like more explanation, though in the context of pair programming specifically.