Practical PHP Refactoring: Remove Setting Method is about guaranteeing immutability or simplifying the interface of an object by throwing away a method.
Practical PHP Refactoring: Hide Method is about information hiding: limiting the scope of a method to be able to easily evolve it later.
Practical PHP Refactoring: Replace Constructor with Factory Method transforms a giant constructor into several well-named Factory Methods.
Rails from the point of view of a PHP developer is about me trying out Rails 3 (again, without prejudices).
Practical PHP Refactoring: Encapsulate Downcast (and Wrapping) is about the PHP version of downcasting: converting primitives and wrapping them in Value Objects.