The Big Bang Theory: "The Panty Piñata Polarization"

Hey, Penny's back! After spending the last couple of episodes mostly on the sidelines, the character who used to be one of the main drivers for the action on The Big Bang Theory gets her own A-story again–although she does have to share it with Sheldon, and it is one of the hoariest plots in sitcomdom.
What we have in "The Panty Piñata Polarization" is the classic "Can you top this?" scenario, often used in sitcoms in the form of "prank wars" between characters, but here seen in the more traditional "revenge for a perceived slight" variation. It begins with Penny snatching an onion ring out of Sheldon's dinner box while he's out of the room. Though the gang immediately warns her to put it back, it's too late: Sheldon spots the disruption, and before he can finish muttering, "Who touched my…," the gang blurts out, "Penny!"
Penny is promptly informed by Sheldon that she has "two strikes"–the first having been marked against her without her knowledge, when she e-mailed him an LOLCat–which everyone tells her is no big deal, because the strikes will only stay on her record for a year. ("You can get them removed early, but you have to take his class," Howard notes.) But Penny, incredulous, immediately decides to test Sheldon's resolve, and subsequently gets banished from the apartment with her third strike. And while Leonard is recommending a simple course of action for Penny to resolve this–"I reiterate: knuckle under"–Penny informs Leonard that it's not just "on," it's "Junior Rodeo 'on.'"
And thus begins the back and forth: Penny tries to refuse service to Sheldon at The Cheesecake Factory, Sheldon complains to Penny's boss, Penny serves Sheldon's food but only after touching it, Sheldon has Penny's access to his wi-fi cut off, Penny disrupts Sheldon's regular laundry night by taking up all the machines, Sheldon removes Penny's clothes from the laundry room while she's not looking and hangs them on a telephone wire, and so on.
What I enjoyed about this episode were the particulars of the "Can you top this," which weren't exceptionally outrageous, but more keyed in to these characters' neuroses: Penny's need to mooch of people with a better grasp of technology; Sheldon's need for regimen, etc. I also liked the funny spin on the standard BBT gag of Sheldon knocking on Penny's door in exact repetitions: first with Penny's manic "Sheldon! Sheldon! Sheldon!" knock, and then Sheldon's defeated "Penny. Penny. Penny." knock.