Big Bang: "Always leave them wanting more"

As always, Monday's episode of Big Bang Theory was very funny, especially the two highlights I am going to point out below.

1) The girl Howard has been dating wants to know what he expects from her and whether or not he is looking for a relationship. Howard hesitates because he is looking for a girlfriend who is hotter, even though, as Penny points out, hotter women are out of his league. Howard finally realizes this and, jumping to the opposite extreme, asks this girl who he has only been on three dates with, to marry him. She thinks he is crazy and walks away, but then he sings her a ridiculous song and asks for her forgiveness, following which she melts and says no one has ever done anything that romantic for her before.
2) Sheldon has been asked to do an interview as an expert on NPR, which is an extreme honor. But Kripke plays a joke on him, feeding helium into his office so while he is answering questions he has an extremely high pitched voice. Sheldon is humiliated, but Raj and Leonard help him realize he needs to enact revenge. So Sheldon organizes a science experiment that produces a large amount of a foamy substance and sets it to go off when motion is detected. Only, Kripke does not enter his office alone, but instead with the university president, dean, etcetera, who are all covered with the foam.