Not the kind of thing I imagine many others would have a use for, or perhaps even find interesting, but I wanted to share my first add-on for the BP5.
This simple board is designed to let you connect up to three Simple Add-Ons (SAOs) to the BP5. This would be handy enough as a source of regulated power, but the board also taps into the rarely used I2C and GPIO pins of the SAO connector. I’m involved in a project currently that will feature multiple SAOs communicating with each other, and this will be helpful for development and debugging.
As for the name, @grymoire had suggested “Plank” a couple months back as a name for BP5 adapters/add-ons, and I liked the idea. Plus it rather looks like a plank from a pirate ship.