Big Bang Theory NimoyLeonard Nimoy, who died last week, made a voice-over appearance on CBS’ The Big Bang Theory three years ago this week. That night, Penny (Kaley Cuoco) bought Sheldon (Jim Parsons) and Leonard (Johnny Galecki) a pair of Star Trek keepsake collectibles. Sheldon, of course, breaks his while playing with it and clandestinely tries to switch his toy with Leonard’s. Then Sheldon’s conscience — Nimoy’s voice — starts to get to nag at him. Tonight, series creator Chuck Lorre used his familiar vanity card to pay tribute to the original Spock at the end of the episode:

Nimoy Vanity Card Big Bang Theory