The Financial Permeability

The Financial Permeability is the fourteenth episode of the second season of the CBS sitcom The Big Bang Theory. It aired on February 2nd, 2009.

Plot Summary
Penny is short on her rent money and so Sheldon lends her some of his spare cash. She feels guilty about not paying it back and still can’t pay her electricity bills. Leonard tries to help and discovers that she paid her ex-boyfriend Kurt’s police fine. Leonard confronts Kurt and eventually he gives the money back. But he doesn’t tell Penny why and she ends up on a date with him while Leonard is left only with Sheldon’s admiration. Sheldon is impressed and improvises a humorous song about the confrontation with Kurt.

Critics
"The Big Bang Theory feels like a show totally happy with who it is and where it is. The dialogue is crisp and silly in equal measure. Everything flows from the well established geeky world which the guys live in and well performed. The show is reliably funny, usually enjoyable and clearly capable of so much more." - The TV Critic's Review

Trivia

 * When Leonard asks they guys what they are doing, Rajesh says that they are on a quest to the Valley of Fire to acquire the Sacred Crown. The goal of the real board game, "Talisman: The Magical Quest Game, 4th Edition," is to reach the center area, called the Valley of Fire, and to acquire the Crown of Command. This is the third appearance of the game, following first season episodes The Peanut Reaction and The Tangerine Factor.
 * At the end of the episode, Sheldon created a song about Leonard and his act of bravery and honor:
 * There once was a brave lad named Leonard. 
 * With a fi-fi fiddle dee-dee. 
 * He faced a fearsome giant. 
 * While Raj just wanted to pee.