Mr. Cooper is full of surprises. During a night out with Amy, Penny and Bernadette, Sheldon let it slip that he's actually pretty good on his feet.
When Penny started spending way more time in Sheldon and Leonard's apartment, she annoyed Sheldon -- who, in turn, attempted to change her personality using positive reinforcement in the form of chocolate.
Sheldon broke into a ball pit hoping the plastic spheres would help him solve a physics problem. When Leonard came to pick Sheldon up, Sheldon narrowly escaped him by hiding in the balls.
When creating a sound mix to keep his anxiety up (which included The Joker's laugh, Godzilla's roar and Darth Vader's breathing), he discovered that adding T. Swift didn't make him anxious like he hypothesized.
When Howard was asked to work with Stephen Hawking, he took full advantage of Sheldon's love of the noted physicist. He made Sheldon polish his collection of belt buckles, do his laundry and, best of all, wear a French maid's outfit.
After breaking up with Amy, Sheldon went full-on cat lady and acquired Dr. Robert Oppenheimer, Enrico Fermi, Richard Feynman, Edward Teller, Otto Frisch and Zazzles.
In "The Good Guy Fluctuation," Sheldon got spooky with his "bazinga" by popping out of the couch cushions to scare Leonard.
Sheldon created the friendship algorithm, which was a flowchart based on a children's book called Stu the Cockatoo Is New at the Zoo, to try and befriend colleague Barry Kripke. Unfortunately, Sheldon got stuck in a loop in his algorithm until Howard bailed him out.
When Howard was given Sheldon's parking spot without his consent, Sheldon became hell-bent on getting it back. Sheldon takes his parking spot so seriously that he was willing to push through his germophobia to sit in Howard's car in the buff.
Sheldon had a panic attack when his World Of Warcraft account was hacked. When he discovered that his wand of untainted power, his gold, and his battle ostrich were stolen, he called the police to report an actual robbery.
The Sheldon Cooper method of finding the perfect spot in a movie theater involves moving to different seats around the theater and yelling out "HA!" to test the acoustics.
Sheldon doesn't drive and can't take the bus because there are no seat belts (and they won't let him use bungee cords anymore). When Leonard couldn't drive him home because he had to work late and Penny couldn't stand being his chauffeur, Sheldon was left with one choice: Howard's moped. It went about as well as you could imagine.
After insulting a judge, Sheldon was thrown in jail. Once he saw the state of the communal toilet in the cell, however, he told the jailer that he was willing to apologize.
Sheldon showed up to a Halloween party in a black-and-white striped ensemble that was supposed to be the Doppler effect. Unfortunately, at a party filled with Penny's acquaintances, everyone thought he was a zebra.
After Amy broke things off with Sheldon, he got "Darlin'" by The Beach Boys stuck in his head. This caused him to realize that there's no one for him but Amy.
Don't give Sheldon coffee. We repeat: DON'T GIVE SHELDON COFFEE. After chattering away about theoretical physics for hours on end, Sheldon took full advantage of his Flash costume and excess energy and ran circles around the apartment.
Sheldon tried to seduce Amy by turning on his inner lothario. He was unsuccessful, but his flamenco dance almost got to Amy. Can you blame her?
After Penny dislocated her shoulder, Sheldon was there to her to make her feel better. It turns out he's got a soft side under all of those neuroses!
In his quest for a non-germ lifestyle, Sheldon was exposed to what we can only assume was a pretty gnarly airborne pathogen. On the bright side, Sheldon got to play "Mystic Warlords of Ka'a" with Leonard, Raj and Howard, all in Hazmat suits.
Sheldon created a robot that could go out into the world for him so that he could stay safe in his bedroom. Because of his sense of impending doom, he missed out on meeting Steve Wozniak at the Cheesecake Factory.
When Leonard asked Sheldon to smile, Sheldon flashed various forms of what can only be described as "murderous clown grimaces." All versions were terrifying, but everyone agreed that the closed mouth smile was the least scary.
Why would Sheldon play bongos? Well, apparently Richard Feynman, one of America's most important theoretical physicists, who was responsible for the theory of quantum electrodynamics, played them. Duh.
When Howard slipped a handful of Valium into Sheldon's warm milk, we learned that Sheldon can't keep any secrets when he's high, not even that his mother smokes cigarettes and that he is, in fact, Batman.
Unfortunately for Sheldon, he witnessed his mother doing the dirty and was scarred. When Howard asked him what happened, he responded with, "I saw my mommy with a naked man and she was trying to be a mommy again."