I'd rather have a motivated group that's poorly organized than a well-organized bunch of goof-offs. Given motivation, though, I wonder whether some forms of organization (especially voluntary organization) work better than others.

I'm particularly interested in situations where there's a significant opportunity cost to collaboration, that is, where any time participants spend on collaborative project X comes at the expense of time they would otherwise spend on worthwhile project Y. How can we get things done together while wasting as little of each others' time as possible?