The Computer Housed Inside a PC Mouse

A YouTuber recently revealed his "Computer Mouse", a fully functional Linux computer housed in a regular sized PC mouse. His inspiration was a plug and play Raspberry Pi based computer he saw housed in a keyboard but wondered if anyone had tried to make a smaller system. Based on the Raspberry Pi Zero the system also has a 1.5" folding colour screen, complete keyboard and runs off of a 500mAh lithium battery. We're not sure it's a system you'd want to use for everyday use but it's another great example of what the Pi can do at such a small form factor!