The act of roadie running with arms out-stretched in an absoloutly flawless attempt to make the run quieter, and increase velocity significantly. This takes prolonged practise, but when mastered is more effective than possibly imaginable.
"Holy shit, the cops just rolled up! Quick everyone Ninja Run the fuck outa this joint!"
"Omg i was nailing this chick last night when her parents walked in, so i had to naked Ninja Run all the way home!"