On last night's episode, Sheldon came to terms with his mortality. Until his consciousness can be preserved forever, Sheldon created a robot to go out in the real world for him.

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Later, Apple co-founder Steve Wozniak makes a cameo appearance. Of course robo-Sheldon would go over and say "Hi".

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Nerds, indeed.

One of my favorite running gags is Penny comforting Sheldon in song. "Soft Kitty" is Sheldon's comfort song, and here is a "Soft Kitty" Sheldon and Penny duet.

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