You won't find Tina Fey, Eddie Murphy, Bill Murray or Adam Sandler on this list
10. Terry Sweeney
Best known for: Nancy Reagan, Joan Collins, Diana Ross
Overshadowed by: Pretty much just Jon Lovitz and Dennis Miller
Why: You've probably never heard of Terry Sweeney and good luck trying to find his fantastic work from his singular season online (there is only one clip that you can find on Hulu). Sweeney was almost revolutionary for network television in 1985. He was an openly gay man who was best known for his impersonations of First Lady Nancy Reagan (son Ron said he was more like his mom than she actually was - watch here) and a killer Diana Ross ("Don't touch"). Dennis Miller gets most of the "groundbreaking" credit for Lorne Michael's comeback season as producer, but it was Sweeney who was trailblazing into the nation's living rooms.