Chandler: (about an ex-girlfriend) I broke up with her... She actually thought that "Sean Penn" was the capital of Cambodia.
Sean Penn is the actor who starred in such movies as Dead Man Walking and Fast Times at Ridgemont High. He was briefly married to Madonna. Sean Penn would later guest star in "The One with the Halloween Party" and "The One with the Stain". By the way, the capital of Cambodia is "Pnom Penh".