The Ficihp mechanical keyboard [Amazon] has an unusual feature: a whole-ass monitor built in to it. You'll be needing the right kind of cable and the right sort of hole on your computer for it to function—and $389 to drop on it in the first place—but the result will be a unique combination device whose utility is presumably obvious to those who want or need it.
Note that while it looks like it might be (or even should be) a whole-ass computer, it isn't. My headline notwithstanding, perhaps it's better understood as a 12.6 inch alt-mode USB-C monitor with a keyboard built-in. You can use your own keycaps!
• 12.6-inch full-color display provides you with a split-screen display and mirror display to expand your field of vision.
• The screen can adjust the brightness, contrast, and other parameter settings.
• Resolution 1920×515, frequency 60Hz, which is close to the screen display resolution provided by this machine.
• 10 touchpoints, allowing it to achieve next to no delay when used. Whatever you tap, you can rest assured that it'll be registered immediately with no dropped inputs.
• RGB backlit 71-key mechanical keys, offering 15 different types of backlight settings and adjustable brightness.
• Support custom backlight recording, to provide you with a different experience and fun.
• Replaceable keycaps for your personalized style.