#40 Armin Shimerman
Star Trek series: Star Trek: Deep Space Nine
Character name: Quark
Shimerman was a main cast member in all seven seasons of Deep Space Nine. He played the role of Quark, a Ferengi bar owner who was a constant thorn in the side ― sometime adversary, sometime confidante ― of station Security Chief Odo. Aside from starring in Deep Space Nine, Shimerman also appeared as Quark in The Next Generation and Voyager, making him one of only seven Star Trek actors to appear in three different live-action Star Trek series.
After his Star Trek stint, Shimmerman went on to appear in several TV series. He most notably played Principal Snyder in the supernatural drama Buffy the Vampire Slayer, as well as Judge Brian Hooper in the ABC legal drama Boston Legal.