To enhance my speech, I nestled one of my favorite specimens between my underwear and shirts in a carry-on bag because I never check luggage on business trips. My banded chunk of the Hebron Gneiss (pronounced "nice") resembled a broken slice of layer cake composed of licorice and cream cheese.Link (via Schneier)
In retrospect, I suppose I could have put the grapefruit-sized specimen inside my sock, swung it around my head like a mace, charged the cabin and attempted to hijack the flight. This, of course, never occurred to me until the zealous inspector declared my rock a "dual-use" item.
"What, pray tell, is a dual-use item?" I asked. I'm afraid I chucked just a little, causing her to glare, withhold a satisfactory answer and call her supervisor. He hefted my rock, scrutinized it for a moment, and agreed that my specimen was indeed a dual-use item, meaning a potential low-tech weapon. During those uneasy moments when I thought I would be detained, I wondered if a doctor's stethoscope would also be declared a dual-use item, since it could be used to strangle a pilot.