Factory Method lets a class defer instantiation to subclasses. Convert the interface of a class into another interface clients expect. Adapter lets classes work together that couldn't otherwise because of incompatible interfaces. Composite lets clients treat individual objects and compositions of objects uniformly.
Decorators provide a flexible alternative to subclassing for extending functionality.
Facade defines a higher-level interface that makes the subsystem easier to use. Chain the receiving objects and pass the request along the chain until an object handles it. Given a language, define a represention for its grammar along with an interpreter that uses the representation to interpret sentences in the language. Mediator promotes loose coupling by keeping objects from referring to each other explicitly, and it lets you vary their interaction independently. The object will appear to change its class.