Put some fun into the life of your UPS guy or other carbon-based life forms that approach your door without their phasers. When they step on the mat, a series of Space Invaders light up randomly and march across the mat. Wikipedia says, "It was originally manufactured by Taito and licensed for production in the U.S. by the Midway division of Bally. Released initially in its native Japan in 1978, it ranks as one of the most influential video games ever created. Though simplistic by today's standards, it was one of the forerunners of modern video gaming."