Shane O'Sullivan has posted what he calls his look at the "amazing technicolor documentation" the CakePHP project offers.
While it's [CakePHP] very impressive from a technical standpoint, that's not what is so pleasantly surprising about it - plenty of open source projects have very talented programmers contributing to them, making technical prowess a starting point for OS projects, not a destination. No, what surprised me was the amazing level of documentation for the project.
Simply put, CakePhp has some of the best, most comprehensive, most relevant and best organised documentation I've seen in an open source project.
He's highly complimentary about the documentation, noting that it wasn't so much about finding a reference to functionality as it was finding a tutorial on how it worked. He notes that the project must have found some way to convince developers to work up this much documentation, as it's more than just the auto-generated manuals several projects have.