I've been on a pipe organ kick lately, more specifically Virtual Pipe Organs (VPO) and I'm thinking of building an inexpensive organ console for the upcoming Maker Faire to show what a VPO can do, and encourage people to build their own.
I've decided to combine inexpensive piano keyboards, a pedal board and preset switches --- materials I already have, and do it as simply as possible. I will be gutting the sound generating parts of the keyboards and using a Highly Liquid MIDI CPU to do the required interfacing. If one already has the keyboards, this project can easily cost less than $100. The MIDI CPU is only $44.
To work within the limitations of one MIDI CPU, I've decided to use 49 note keyboards. 61 note keyboards are the norm for organs, but they are much harder to find cheap or free. Using 49 note keyboards should allow me to interface everything with one MIDI CPU.
More details as I work them out.
Here is the Picasa album : https://picasaweb.google.com/tkarches/LowCostVPO