ObjectWare
Crowd-sourced documentation and tutorials by the Cocoa developer community
ObjectWare is the idea of selling (well, licensing, which may or may not cost money) code in the form of objects. It's a pretty neat idea, but unfortunately, it doesn't seem to have taken off (possibly because of the market... many programmers seem to look askance on object collections with a kind of "Not Invented Here" mentality). But see topics on Unit Testing.
Some classic ObjectWare is the MiscKit, TheOmniGroup's frameworks, et cetera.
