As part of a project I have been contracted to complete, I have developed an I/O expansion board for the BB and BBB. The board provides 32 analog input channels and breaks out 32 of the GPIO’s (conflicts with the HDMI and LCD), and does level shifting to 5VDC for use with off the shelf relays. The relay drivers are setup to use the sainsmart relay boards, and connect directly to them by ribbon cable.
The organization that contracted me is permitting me to resell these boards to the general public, and I have retained the rights to the design. If there is interest, I will make them available for sale. I am interested in knowing what would be a good price for these boards, and if there are any modifications that people would be interested in to make them more useful. They are currently being used as a robotics control board for driving actuators with a feedback position sensor and as mentioned, the board conflicts with the HDMI pins.