Legend has it that Douglas Engelbart invented the mouse in 1968.
But did you know that German television manufacturer Telefunken released a "rolling-ball" device just a few months earlier?
From a technical perspective it actually closely resembles the kind of mouse that we ended up using until the late 90s.
The German patent office declined a patent due to a "lack of inventive step".
Pretty sure the original design is even older than that
Generalistic and moderated instance.