This is a bit of a weird one, but if you're looking for examples of how different social groups use language to cement their in-group status, then have a look here for expressions used by fans of science fiction and fantasy.It's quite interesting stuff from a Language Variation perspective (like how different social groups use language in their own communities of practice) and could also be useful for Language Change when thinking about how words go through processes of abbreviation in contexts like this. A good example of this is the suffix -zine, which itself derives from a clipping of magazine, but is now used in all sorts of contexts (fanzine, e-zine, crudzine).
Communities of practice
A community of practice is an aggregate of people who come together around mutual engagement in some common endeavor. Ways of doing things, ways of talking, beliefs, values, power relations - in short, practices - emerge in the course of their joint activity around that endeavor. A community of practice is different as a social construct from the traditional notion of community,primarily because it is defined simultaneously by its membership and by the practice in which that membership engages. And this practice involves the construction of a shared orientation to the world around them - a tacit definition of themselves in relation to each other, and in relation to other communities of practice. The individual constructs an identity - a sense of place in the social world - through participation in a variety of communities of practice, and in forms of participation in each of those communities. And key to this entire process of construction is stylistic practice.
And it also gives me an excuse to use a picture of a cylon.
