Via MacOSXHints, a great article about Cocoa’s text bindings and the Amazingly Cool Things you can do with them—like, implement a standard keystroke to wrap a piece of text in some HTML formatting in every Cocoa text field in your whole system. Also a list of default bindings as shipped in Mac OS X, and a list of all the usable selectors that you can combine with keystrokes to get some really cool things to happen.