When you pick your nose while playing Halo 3 and stick it to your lower quad just above your knee. You plan to flush it once your done playing, but you never remember. When you finally do remeber, the booger is gone and you wonder where you lost it.
Guy 1: "Man, I love raping the crap out of people who don't know how to XBOX."
Guy 2: "Oh, yeah. I know. Oh man, that is a big booger.
Guy 1: "Make sure you treat that booger right, or it might become one of those runaway boogers I been hearin' about."