Sneakers, my favorite heist movie, features some plot elements that involve the NSA. It came out in 1992, when that agency wasn’t particularly well-known–o halcyon days!–and so it has this little exchange between Robert Redford (“Martin Bishop”) and Timothy Busfield (“Dick Gordon”) to introduce it to the audience.

Bishop: Sorry to waste your time, gentlemen. I don’t work for the government.
Gordon: We know. (Flashes ID) National Security Agency.
Bishop: Oh, you’re the guys I hear breathing on the other end of my phone.
Gordon: No, that’s the FBI. We’re not chartered for domestic surveillance.

Ah ha ha ha ha! Ha ha! Ah ha ha ha ha. Heh.

Bishop: Oh, so you just overthrow governments–set up friendly dictators.
Gordon: (chuckling) No, that’s the CIA. We protect our government’s communications–try and break the other fellas’ codes. We’re the good guys, Marty.
Bishop: Gee, I can’t tell you what a relief that is. Dick.