'30 Rock': The 15 Best Guest Stars, Ranked

(3) Chris Parnell as Dr. Leo Spaceman

Feeling ill? Don’t let this man anywhere near you. One of “30 Rock’s” best running gags was this grossly incompetent doc, played by another former “SNL”-er, who penned “The Cigarette Diet” and treated the “TGS” crew with not-so-sage medical advice: “Sounds like you could use a little R&R… rum and Ritalin.” Dr. Spaceman (pronounced Spa-CHEH-min, of course) got a happy ending, though: In his final appearance ... more 

(3) Chris Parnell as Dr. Leo Spaceman

Feeling ill? Don’t let this man anywhere near you. One of “30 Rock’s” best running gags was this grossly incompetent doc, played by another former “SNL”-er, who penned “The Cigarette Diet” and treated the “TGS” crew with not-so-sage medical advice: “Sounds like you could use a little R&R… rum and Ritalin.” Dr. Spaceman (pronounced Spa-CHEH-min, of course) got a happy ending, though: In his final appearance this season, he was promoted to U.S. Surgeon General. God help us all. less