There's an obvious word for this but I can't think of what it is

ok, quiksourse

I guess I'd just call it a fact sheet.

Pocket guide.

Brain dump.

quick reference guide

quick start

getting started guide

Quick reference or reference guide

That sounds like "Spark Notes" for the web. So how about "___-Notes", where "___" could be any play on "Spark" that's not copyrighted? "Web-Notes", "XYZ-Notes" (where "XYZ" is the organization's acronym) or just "Notes" come to mind. But now I can't get rid of this nagging feeling that there's got to be a better play on "Spark".

SparkNotes seems to itself be a takeoff on "Cliff's Notes," which was a paper version, famous for being a way for high school students to bluff their way through assignments without reading the book.

Ooh, cheat sheet?

I like "cheat sheet" --- unless the overall tone on the rest of your website is very dignified. Is it?

Not actually sure, I'm making recommendations to someone else who will make the decision. It's a contender though.

at-a-glance

"Your rights at a glance."

Oh that's good!