This is a Boolean logic module. It has two channels each with two inputs and gate outputs. The logic function of each channel is selected by the position of the potentiometer. The logical operations available are AND, NAND, OR, NOR, XOR, XNOR. For mroe information check out this PDF file.
Boards are available now. Price for 1 board and 1 preprogrammed PIC $16.
There are unfinished aluminum Eurorack panels available for this project. They are $8 each. For more information on my panels, check this page. If you'd like to drill your own, here's the template that I use, print it out at 300dpi