I built myself a HUD using a VuFine LCD and a raspi Zero W. It runs a custom TUI I wrote for myself that provides an interactive terminal session surrounded by configurable text widgets.
Currently, I have widgets configured to display the date/time, the weather (near-term and week), and CPU/Mem utilization. With the main display running my combined to-do/calendar app to help keep me organized.
It’s tacky as hell, bulky and exposed wires, but I love it.