This
site is dedicated to everyone interested in Serge Modular Music Synthesizers
M-Class
M-Boat with rack ears, including power distribution - $300 USD
PS2a Power Supply - $225 USD
Thanks to Ty Hodson for pulling M-Class module information together from various sources. Other references include "Introduction of the Serge Modular Music System" by Rich Gold, Darrel Johansen, and Marina LaPalma