A post from the hackernews thread had a lot of that info:
Link to project website: https://senseable.mit.edu/flatburn/
Link to assembly guide: https://github.com/MIT-Senseable-City-Lab/OSCS/blob/main/Bui…
Link to bill of materials: https://docs.google.com/spreadsheets/d/1-fR-0hTxHKbjaRf8DbH6…
Naively searching for every lines of the bill of materials gives me around $300, with a handful of items being around $50 and everything else under $5. I’m sure a hobbyist could find the parts for cheaper, especially things like individuals connectors that I found for around $5. I’ve seen them go as low as $0.25 when bulk purchased.
Disclaimer: it’s possible that some SKUs led me to the wrong products. I am not into electronics. I encourage you do to the same exercise before drawing conclusions.
Without direct support in Borg you’ll need to use something like FUSE, for example with a quick search I found: https://github.com/matteoserva/MegaFuse
Basically use fuse to mount the mega drive to a local folder and point Borg at it. This will likely be slow but it’ll he the job done. Or you can o it in two steps. Backup to local drive, upload the wholefoldedr you backed up to Mega.
Seems odd to read about it on medium.