The comedian, a small robot named Data, takes the stage.

Rising from a crouch, as if psyching himself up for his audience, he waves. "It's an honor to be here," he says in a voice that makes him sound like a geeky adolescent boy with a helium-sucking addiction.

He launches right in to his routine, telling a doctor-patient joke, a Swiss army joke, old chestnuts from Fred Allen and Groucho Marx such as the line about why television is called a medium -- it's neither rare nor well done. (Rimshot, please.) His owner and programmer, roboticist Heather Knight, looks on with amusement.