Lara: Stop it, Lara. You're starting to sound like Dad. It's like they're the remnants of some lost civilization! ...okay, now I really sound like Dad.
In a collection sidequest, Lara has a Nerdgasm over finding a jade horse from the Kublai Khan era. Further investigation reveals the words "Made in China". You can practically hear the disappointment in Lara's timid little giggle. Another one of the collectibles seems like something exciting at first... until Lara discovers a price engraving of "49.95."
If you wait around the old PT boat for a bit before going to link up with Alex, Sam will accidentally fire off one of the boat's still-functional machine guns. While responding to Reyes's admonishment to be careful by saying she knows what she's doing.
At one point on Shipwreck Beach you can talk to Sam and asks how she's passing the time, and she's reading an old copy of Robinson Crusoe and commenting on how it's a cruel irony.
Some of the conversations between the bad guys that you can overhear are pretty hilarious.
Returning to the Shantytown can lead you to two guys arguing about borrowing a book in return for smokes.