[Quiet Man Cometh]

I don't watch the show regularly, but it's pretty darn funny. I like Sheldon even though he's something of a jerk at times. I like the one where Penny is trying to convince Sheldon to get Leonard a gift for his birthday. "Just tell him it's a non-optional social convention."

ThinkGeek.com as a t-shirt for sale:

*knock*knock*knock*
PENNY!
*knock*knock*knock*
PENNY!
*knock*knock*knock*
PENNY!