Since a while, we have created the GRIS (Groupe de Recherche en Immersion Spatiale: Research Group in Spatial Immersion) at the faculty of music of Université de Montréal.
One of our first productions, the Octogris plugin, already available since a while on Google Code, is now ready for download with the manual and the tutorials for Digital Performer, Logic and Reaper audio sequencers.
This plugin was originally designed for octophonic spatialisation.
But we have developed this idea and it is now possible to do 32 tracks by 32 speakers if you like (and if your sequencer allows it…).
OSX Leopard and Snow Leopard compatible.

Plugin web site:
http://www.iact.umontreal.ca/site/?page_id=1091&lang=en
Google Code download:
http://code.google.com/p/octogris/downloads/list

English manual online:
http://www.iact.umontreal.ca/octogris/en/home.html