Recently divorced Dr. Howard Sheinfeld moonlights as the on-call physician at Clark Street Hospital in Chicago so he can keep up with heavy alimony payments. This was the first of two emergency room assignments for supporting player George Clooney. His second came 10 years later, when he landed the breakout starring role of Dr. Doug Ross on the other, more celebrated 'ER.' Another 'E/R' cast member who went on to bigger things: Jason Alexander, who plays hospital administrator Harold Stickley.