NodeBox is a Mac OS X application that lets you create 2D visuals (static, animated or interactive) using Python programming code and export them as a PDF or a QuickTime movie. NodeBox is free and well-documented.
This is a small Cocoa application that creates a hierarchical menu, in the dock, and when it is the frontmost app, in the menu bar, of your apps. It only shows apps. If a folder has a single app, it hoists the app up, so no subfolders of exactly one app.