Wil Wheaton debuts as the new Professor Proton
Who knew you could make your own hovercraft using household items?
Go ahead and put that old Turbo Tax CD to good use!
Sheldon is elated and giggling like a school kid.

Credit: Michael Yarish/CBS
I spoke too soon.
All bets are off when Professor Protons doorbell rings and astronaut Howard Wolowitz is on the other side.
Did Sheldon hit his head?
Howard explains that if Sheldon wants to be on the show, hell have to ask for Wils forgiveness.
Howard knocks on Wils door, apologizes, and presents a repentant Dr. Cooper.
Wil accepts Sheldons apology and suggests that Amy come on the show to support female scientists.
Although he didnt shout it, you could see in Sheldons eyes that he was mentally screaming.
Sheldon calms down and relays the offer to Amy, who is uninterested in being on television.
Hasnt she always supported women in science?
He emphasizes his plea with an enthusiastic, You go girl.
Amy confesses that she doesnt want to get in the middle of Sheldons admiration for the show.
Newsflash: Its not just Amy.
Sheldon promises to change.
He even swears he will wear a backwards baseball hat sporting the Gryffindor logo to show his commitment.
But the true test is when he encourages Amy to be a guest of Professor Proton.
Our Sheldon is maturing.
And hes kind enough to go to the roof to scream out his frustrations.
Thats growth, people.
Howard suggests Leonard show Bernadette an early manuscript and she is thrilled with his progress.
The one wrinkle: Will his wife be irritated that the main female lead is based on Penny?
The screen dissolves into a murder scene.
Howard, Raj, and Stuart are all suspects.
Logan Dean gets his detective on with a spunky blonde belittling him.
Leonard jerks from the fantasy.
He did base the mean girl on his wife!
Leonard keeps his mouth shut.
However, since Penny and Bernadette are best friends, the truth comes out.
And a little snarky.
Not to mention mean.
Im not a Bond villain.
Im just a regular guy with a regular enemy list.
BERNADETTE: I dont know how people who arent on bed rest keep up with the Kardashians.