Defaults Manager is an editor for the User Defaults preferences database on Mac OS X. It allows you to easily view, edit, delete, and backup preferences, and can be used to view and change the preferences in almost any application. It is useful for developers that want to make sure their preferences are being stored and changed correctly, and can be used to unlock features that previously required the use of Terminal.
Yafca (Yafca's Another Flash Card Application) is an application for creating and viewing flash cards in an arbitrarily complex hierarchy of decks. It has built-in pinyin Unicode conversion and convenient font resizing, which makes it ideal for learning Chinese or other Asian characters.
LifeSaver is a Mac OS X screensaver that simulates Conway's game of life on screen. The starting configurations for the cells are randomly selected from predetermined configurations and from randomly generated configurations. MandelSaver is a Mac OS X screensaver that draws colorised Mandelbrot images on the screen. The position and coloration of the subset of the fractal displayed is randomly selected.