Sheldon invents his own version of rock-paper-scissors in this episode which includes the addition of a lizard and spock naturally.
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The guys meet Wolowitz's soul mate, Dr. Stephanie Barnett (Sara Rue) in this episode of The Big Bang Theory.
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Leonard goes on a date with Stephanie (Sara Rue), who Wolowitz is convinced is his soul mate.
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The Big Bang Theory Season 2 Episode 8 Quotes

I am not going to watch the Clone Wars TV series until I've seen the Clone Wars movie. I prefer to let George Lucas disappoint me in the order he intended

Sheldon

Raj: I'll tell you what, how about we go rock-paper-scissors?
Sheldon: Eww, I don't think so. Anecdotal evidence suggests that in the game of rock-paper-scissors, players familiar with each other tie 75-80% of the time due to the limited number of outcomes. I suggest "rock-paper-scissors-lizard-Spock"