Wheel-Like Data Visualization With MooWheel
MooWheel is a mootools based script which visualizes data and connections between items like a wheel.
MooWheel uses CanvasText and ExCanvas libraries other than mootools which are already included in the package.
Usage of this data visualization script is pretty simple. You simply create a data array, add a canvas tag and call the function.
There is a very nice demo here.