A Jug as a musical instrument reached the height of it's popularity in the 1920s. The jug is a glass or stonewear jug played with the mouth with an embouchure like a brass instrument, buzzing the lips. The jug does not actually touch the players mouth, but acts as a resonating chamber.
Although the jug is used primarily as an acoustic instrument, they have been known to be played amplified from time to time. Snoop Dog is reportedly a modern day jug player. Who knew???