Under Tiger there was a clever third-party iTunes plug-in called iVisualize which allowed you to make your own iTunes visualisers using Quartz Composer. Under Leopard, it's not even needed any more -- simply make a new Music Visualiser type composition in Quartz Composer, and drop it into the Compositions folder of your library. You can also make your own iChat Video Effects by the same route -- just choose Image Filter as the composition type. Similarly, the Image Transition composition type can be used for Keynote transitions. For more info, see the Quartz Composer release notes. If you've got the Developer Tools installed, you can also examine the examples at /Developer/Examples/Quartz Composer.

	Read more at MacOsxHints
	feeds.macosxhints.com/~r/macosxhints/recent/~3/187358973/article.php