This may interest you; might not be what you were asking for. I haven't built one, but keep an eye on it and dream of free time to surface mount solder and poke

This may interest you; might not be what you were asking for. I haven't built one, but keep an eye on it and dream of free time to surface mount solder and poke around with it. The repo used to have a cost estimate and think it came out to around $100 but my memory may be fuzzy. https://github.com/joeycastillo/The-Open-Book https://github.com/joeycastillo/The-Open-Book