A cool Wiki with very helpful tips related to Prototype and Scriptaculous libraries : the Unofficial Prototype and Script.aculo.us Wiki.
While getting less marketing that some other libraries, Prototype and Scriptaculous are very well-designed and effective libraries. The only thing they need is more chat places. Such a wiki is a great step to help people discover or share their experiences with the libraries.
As soon as I’ll have some spare time, I’ll probably open a web site dedicated to those as well, especially to summarize available resources and to bring up a discussion board.