Valve 'open-sourced' the Steam Machine's e-ink screen. It turns out to be an off-the-shelf Adafruit part (gamingonlinux.com)
Valve released the design files for the Steam Machine's front-panel e-ink screen so owners can build or print their own faceplate instead of buying one. The catch, surfaced in the thread: the display is a standard Adafruit 5.83-inch e-ink panel, and Valve explicitly won't sell its own.
So 'make your own' collapses to 'buy a commodity panel and Valve's mounting files' — and readers question modding a $1,049 prebuilt device at all.