Earlier this month the New York Times reviewed Aquamind's NoteShare. Fallows does a good job pinpointing the crux of the difficulty of computer supported cooperative work (CSCW) -- simple interface usually means limited functionality while robustness usually means the need for an entire IT department. NoteShare sounds like a comfy balance. Looking forward to the PC version later this year. I'm getting tired of emailing documents and creating Yahoo groups for every conference panel proposal I'm on.
While asynchronous collaboration certainly works for most academic work, there are often times early in the process (identifying the unifying theme of several projects) and late in the process (close-editing of collaboratively-written documents) when synchronous collaboration would be nice.
I seldom sit down at a computer with another person, but in co-authoring an article with Jason Swarts when I was in Raleigh last year, we'd meet in a coffee shop with a laptop and pass it back and forth. Extreme writing, as it were. I found the process extremely rewarding. One of my main concerns about teaching composition is that by having students writing in isolation all the time, they can develop bad habits or at least never see other ways of writing that they themselves might benefit from. They develop a mere knack when learning a craft is the goal.