A couple of days ago I saw a website for sharing code. www.openprocessing.org/ visuals/? visualID=2356 (remove spaces.) It has the application for which you were viewing the code, followed by a box with the code. My first instinct was that it should be a wiki, so it would be easy to quickly develop code.
I should think the page would include links to the first-posted or latest maintainer-approved version of the app.
It might also be reasonable to support straight Java, and Processing, the language used on the site tat inspired this idea.
Anyway such a site would bring open source collaboration to a new level.