Yep, some kind of wiki (that is kept up to date, and yes, that needs people who write) would be fancy for all the Linux/Unix tech. Explanations which thing does what and maybe some practical howtos for setup and configuration of the described component. Esp. lately there was a lot of development introducing new stuff, graphic, audio and misc..
The Gentoo wiki had a lot of good stuff, even some other distribution folks linked to it since it often contained some generic procedures that would probably work everywhere but sadly it lost a lot of content and is still awaiting a larger rewrite.
Though Gentoo dev / maintainer team is considering the idea of having an official Gentoowiki (the old one was a Mike Valstar "fan project" (it was his hoster who didn't pay some bill and went closed and Mike not having any access to the servers and also lacking a recent out-of-serverhouse backup)).
Stop TCPA, stupid software patents and corrupt politicians!