Thereβs Whole Computer Inside This Mouse

[Gadget Industry] bills it as βa PC inside a Mouseβ, but that depends on your definition of a βPCβ. This is a Personal Computer inside a mouse, yes, but thereβs nothing IBM-compatible about the tiny ARM board he squeezes inside whatβs normally a peripheral β it actually started life as a smartphone, which only takes this build up a notch compared to starting with a single-board computer like a Pi.
Specifically, he starts with a Galaxy S21 5G. Starting with a Samsung means he can leave the stock Android alone and just take advantage of Samsungβs DeX desktop mode, rather than layer a Linux environment on top or replace the operating system entirely with something like Postmarket OS, which are both viable options.
With the battery compartment removed, the phone guts fit with shocking ease in the once-wireless mouse. Of course thatβs not a great thermal environment, but thatβs what the brass is for. It acts as a heat spreader, which is about as much thermal management as the phone had from the get-go, so it should work well enough. It seems to in the video, certainly. If thermal throttling is a concern, while itβd be hard to fit in a mouse, thereβs no beating liquid cooling.