21.   He sits in his wicker rocking chair and taps his foot to old salsa albums.

22.   He taps his foot and nods toward the drummer who will solo next.

23.   He rubbed his eyes, sipped coffee and tapped his foot in an apparent effort to stay awake.

24.   He was tapping his feet to the salsa and bantering with the disk jockeys.

25.   He was there, waiting for us, tapping his foot impatiently.

26.   He tapped his feet to the music, and he joked, the acid of the last few weeks drained from him.

27.   He was leaning on the hood of a parked car, with a hand on his hip, tapping his foot and bobbing his head.

28.   He tapped his foot.

29.   His father took the wheel, put the gear in neutral and tapped his foot lightly on the brake.

30.   Horvitz, who has a PhD in computer science and a medical degree from Stanford University, is an intense man who incessantly taps his foot during an interview.