One of a very few things that bug me about Panic’s Coda code editor is not being able to switch keyboard focus between editor pane and file list pane. It’s especially required when editing files directly on ftp server, where “Open quickly” menu command doesn’t work.
Using the Coda’s Objective-C API I managed to overcome described problem by making a simple plugin that does just one thing: switches keyboard focus between two panes. You can find plugin, and it’s source code, below. Feel free to do anything you want with it.