just a list of some cool tech i find. This will be a list of all sorts of offensive, defensive and everything inbetween tech, as with documetation and links
https://www.keydemon.com/en/keydemon/68-keygrabber-air-usb-hardware-keylogger-5906874492116.html tiny, compact usb to usb keygrabber, $21
https://maltronics.com/products/malduino-w an over wifi, keystroke injector, usb and usb c based, $51