The Big Bang Theory's Sheldon Cooper is not crazy. He is sure, because he's mother had him tested. This is just one of the "facts" that TBBT fans know very well about one of the quirkiest characters in TV history.

The Big Bang Theory is keeping CBS charting high on Thursday night ratings. Now on its sixth season, the sitcom is still breaking its own rating records. Its Nov 15 episode "The 43 Peculiarity" is the show's highest rated episode ever. This episode follows Howard and Rajesh as they try to figure out Sheldon's mystery afternoon activity. Offended by his friend's meddling, Sheldon shocks the two with a hoax video. He makes it appear as though he has created a portal to parallel universes.

"The 43 Peculiarity" is ushered by a preceding episode featuring recurring guest star Wil Wheaton as himself. This episode is peppered with references to children's stories, from Pinocchio to Wizard of Oz, to Alice in Wonderland.

"So the heart you got from the wizard givin' you trouble?" Penny asks Sheldon at The Cheesecake Factory. She serves him Long Island Iced Tea. Sheldon avoids drinking alcohol, but he thinks the Long Island is just another fancy name for regular iced tea.

"Get the Mad Hatter on the horn, I'm having a tea party!" Intoxicated Sheldon later tells Penny.

TBBT Quotes: Sheldon Cooper as Batman

The role of Sheldon Cooper has given actor Jim Parsons two Emmy nods as Outstanding Lead Actor in a Comedy Series (2010 and 2011).

Below is Sheldon's dialogue with his roommate Leonard from TBBT Season 2 Episode 1: "The Bad Fish Paradigm."

Sheldon: I wouldn't tell you the secret. (pause) Shhhhh!!!!

Leonard: What secret? Tell me the secret.

Sheldon: Mom smokes in the car. Jesus is okay with it, but we can't tell dad.

Leonard: Not that secret, the other secret.

Sheldon: (Whispers) I'M BATMAN! Shhh...

This Thursday, Sheldon attempts to nurse sick Amy Farrah Fowler in Season 6 Episode 10: "The Fish Guts Displacement." Will he sing his get-well-soon song "Soft Kitty" to his girlfriend?

Tumblr accounts sheldonappreciationblog, impliedbazinga, and bigbangtheoree are just some of the blogs dedicated to the humour of Dr Sheldon Cooper.

Click 'Start' to see what some Sheldon Cooper fans are blogging on Tumblr.

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