Make:

LEGO minifig patent from 1979! [via @grantimahara]

Update: A reader writes in with this clarification:

Its not a patent but a design, in the legal sense (and practical). The difference is subtle, a patent is protects something like an apparatus (thing), a method of doing this apparatus and possibly how to operate said apparatus (let's stay away of medical/chemical patents for now). Unless there's a "technical effect" you cannot have a patent. A Design protects a shape/form of a product, toys usually fall under this class. Things get interesting when the shape has a technical effect (i.e. providing better grip in a hand mixer) then you might actually be able to get a patent on a design.