Quick thoughts: collaborative achievement

So I've recently been thinking a lot about what I've come to call collaborative accomplishment or collaborative achievement (which term works better?). And it's sort of a meta concept for me, really, encompassing neatly a number of powerful experiences and human dynamics that have cropped up in different places, a sort of unified field theory of social dymanics.

My understanding of the workings of online (and other) social dynamics is all rooted, so much as I can, in the basics... Why are people so engaged with games? They're sandboxes, enabling us to experiment, challenge ourselves, and learn to win. What's with the odd twistings of online social identity? Again, it