Had this, on a generic Ubuntu Linux workstation. evrouter to watch for a specific HID device "keypress" and remap onto a hotkey, KDE Plasma to have that hotkey

Had this, on a generic Ubuntu Linux workstation. evrouter to watch for a specific HID device "keypress" and remap onto a hotkey, KDE Plasma to have that hotkey trigger a screen unlock script, another script to lock the workstation if the HID device goes missing from USB tree. Nothing special (or secure - the whole setup hinged on the specific device ID, and would have worked with any other device of the same type), but a bit hairy.