From the 1930s to the 1970s, Aerolux Light Corporation manufactured "artful gas-discharge light bulbs," lightbulbs containing tiny sculptures that glowed when switched on. From Wikipedia:
Aerolux gas discharge light bulbs contained low pressure gas, either neon or argon, or a mixture of the two. Also within the bulb were metal sculptures coated with phosphors. These phosphors fluoresced when excited by glow discharge. Because glow discharge occurs readily at 110-120 volts AC, one could use these bulbs in standard household lamps in the United States.
(via This is Colossal)