Switchblade - West Side story.
Nun-chucks - Bruce lee and kung fu fighting movies
Butterfly knives - Hit Girl, Big Trouble in Little China, etc.
I have owned many Bali songs over the years. Like my dads boot knife they serve one purpose for which they are well designed. In Olongapo I was sitting in a bar called the West Forty. We all carried balisongs for self defense. SP or gate guards would confiscate them if we were caught. But a new one costs about $1.50. Sitting with a group of young Marines, we were practicing opening our Butterfly knifes quickly. Pretty Filipina Waitress (seriously not bar girl) comes over laughs and says we are too slow. Reaches into her tight jeans and spins open two knives open at blinding speed. She then explained the knives other purpose and why they are called butterfly knives. Despite being pretty not a single Marine was willing to go out with that girl.