Motivation for this proposal: I've noticed that each SE site has a slightly different culture. For example, some sites:
do not allow partial answers in comments (e.g. Interpersonal Skills)
frown upon writing an answer to a question that is likely to be closed (e.g. ELU)
do not allow assumptions of gender when it isn't known (e.g. Academia)
control question quality more or less tightly (e.g. ELU very strict, ELL much less strict)
Here are some other examples of cultural differences among sites:
At Academia, there are often lively debates involving a large number of participants; moderators are pretty tolerant but if a debate start to get out hand, a moderator will often move it over to Chat, which usually slows things down enough to cool people off
At ELU, the review queue is rather overwhelming
Here at Spanish Language Beta, we allow questions to be written in either English or Spanish or a combination
Recently I spent a little time at an SE site I wasn't very familiar with, and looked around a bit at another site that I hadn't visited in a long time. I realized it would be helpful for each site to have its own cheat sheet with a quickly read bullet list showing the key features and characteristics of the site, that make it unique.
Such a cheat sheet could include:
Some of the reasons why regular participants there like the site -- this would show newcomers what the site has to offer
Local policies that might be tighter or laxer or in some way different than the average SE site
Optionally, a theme song that might have been selected by community consensus
Optionally, a list of all the countries the regular participants live in
Links to important pages that it would be helpful to have listed all in one place -- for us, this would include links to
the tag housekeeping page
the resources page
the list of commonly used comments (e.g. welcome -- your post is problematic in such-and-so way)
Note, I was thinking of proposing this as a feature request at SE Meta, but then I thought, if people here like this idea, we could create such a thing for our site, and maybe it will set a trend!
I have a proposal for a theme song, but I'll wait to post that (separately). First I guess I should wait and see if there is any support for the general concept.
Here are a couple of analogies for the proposal:
Let's say you can program in Java, and you need to do some maintenance of a program written in C++. You look around for a book written for a target audience like you -- already familiar with basic programming concepts, but in need of a succinct guide to show you how C++ is different from Java.
Let's say you are an experienced Settlers of Catán player (this is a strategy board game in the general genre of games sometimes called "Eurogames"). Someone has lent you an expansion. The expansion's rule book has a separate section written specifically for people who are familiar with the basic (unexpanded) version. This enables the players to get a quick start to the expansion.