Reiterating some other blogs, I point to the Tim Gowers's project, asking the question "Is massively collaborative mathematics possible?" Like others, I intend to show it to students, and discuss the ways in which it is like -- and unlike -- less massively collaborative research.
A complaint I often hear among faculty is students in Computer Science (and, I would imagine, mathematics) don't realize how social research in CS (and mathematics) usually is. The stereotype of sitting along in your cubicle working on code all day is out of touch. CS papers generally have many authors; it actually seems research in the liberal arts is less interactive, with people toiling, solo, on their own book projects. If the project does just a little to correct that impression, it will be a success in my mind.