Basically, photograph any game systems, parts, and accessories you have, or write articles/fill in or edit existing articles. Recruiting more people to contribute would be cool, too.

ok mate, i'll help when i can, already talked to one of my mates.

This is a very interesting project; something like this would have been extremely useful years ago. I won't have access to my game collection for a while, but I do plan to contribute to this site. A wiki that has many teardowns and comprehensive development guides for older systems in an easily accessible form would be a god-send for homebrew development (especially for more obscure systems). 

Everything would have been extremely useful years before it was developed or created. Unless it was a threaded lid for threaded glass jars. That would be silly.

I could write dozens of articles in a day, but I'm completely at odds with the editing tools of Wikia (not that I am a Wikipedia master), and my writing style is schizophrenic at best. Not good for a read, and hard to follow. Also, this, being an encyclopedia, is not suited for a lot of meandering nonsense. My collection and experience only touches the fringes of the obscure, so I can't write valuable stuff like "How I met the head programmer of Polybius at a bar", but more along the lines of "My friend once had his artwork published in the letters section of EGM". I have a working 3DO. Wow.

But hey, anything and everything is welcome. Even stuff tangentially related to classic gaming, like the pyramid scheme contests in game magazines.