Heres a place to share the coolest of all phases...Phrases coined from firearms related things.
Number 1: Riding Shotgun

Riding shotgun was used to describe the guard who rode alongside a stagecoach driver, ready to use his shotgun to ward off bandits or Indians. In modern use, it refers to the practice of sitting alongside the driver in a moving vehicle. The phrase has been used to mean giving actual or figurative support or aid to someone in a situation.The phrase was coined in 1919.
thanks Wikipedia