@Annie, I'll take a shot at this with some examples of insider language with my crew.
We used to have someone who constantly edited his posts. His screenname was "Pyee". Therefore, when someone edited their post, instead of starting the edit off with "Edit:..." they started using "_Pyeed:...".
Another one would be a reference to our business moving. We used to be in Illinois. In order to avoid a new tax law, we moved across the boarder into Wisconsin. Meanwhile, if someone posted a forum topic in the wrong forum, we mods would move it. The community made the connection between between moving the business and moving threads. As a result, when something was moved to our Off Topic forum, a member would inevitably reply with "Beloit" or "Beloited". And then, "Beloit" became a verb.
This vocabulary makes absolutely no sense to anyone who does not know where in the world these words came from. If a visitor to read at the bottom of a post, "Pyeed: looks like the mods beloited this. :/", it could strengthen feelings of exclusion, whereas their use among members made them feel special because they got the reference.
Pyeed: I believe the more obscure the language/reference, the more powerfully it affects readers.