6. Jack Black
Best Known For "School of Rock", "Kung-Fu Panda" and Tenacious D
Appears In "D.P.O." 1995 Jack Black had already made brief appearances in some well-known feature films (Demolition Man, Waterworld . . . the Neverending Story 3: Return to Fantasia), but its in an early Season 3 episode that we see him really working those acting chops. Playing the role of arcade-clerk Bart Zero Liquori, he is questioned by Mulder and Scully as they investigate the deaths of several people struck by lightning. It transpires that the culprit is his close friend, Darin Peter Oswald (played by Friends favourite, Giovanni Ribisi), whod gained great electrical powers after surviving a lightning strike. Oswald had been using these powers for his own entertainment and revenge, but its not long before he suspects that Liquori has been getting a little too close to the agents. Unfortunately for young Mr Black, this means hes got a one-way ticket to ride the lightning.