Roger Bolton from eskatonia has put together a great Quartz Composer VJ patch complete with on screen previews and keystroke triggering of clips.
Quartonian is designed to be run in Quartz Composer at full screen and thus has very few on screen controls, in fact with a press of the “~” key you can toggle the whole onscreen display on and off. This makes for a fairly steep initial learning curve for users but, you soon get a feel for using the keyboard and mouse.
Clips (up to 24) must be loaded into ‘Image with movie’ nodes from within a macro patch using Quartz Composer’s editor window to begin. *Hint* it’s the little blue one at the top 
Also on the eskatonia site is a guide to Quartz Composer for VJ’s with lots of useful links and examples.
Until visiting this page I didn’t realise that you could load .qtz files into ‘Image with movie’ nodes. For example, the ‘Audio Barcode’ .qtz file from the site which reacts to audio input can be loaded into a patch and used as a mask on another clip.
Both Quartonian and the other examples on the site are released under attribution – non commercial – share alike creative commons licenses so users are free to modify and create derivative works.
Technorati Tags: Quartz Composer
I’ve had a play with your bikelights project as well, pretty cool and
I the first thing I thought was
“wow we should really combine these two”?
Quartonian is also licensed under Creative Commons, would you be
interested in trying to work together
on a combined VJ mixer?
seems to me it could maybe complement each others areas of knowledge
contact me if you’re interested visuals@eskatonia.com
Roger
Eskatonia Visuals