After laughing at this thread, I remembered it was time to change out my plugs. When I got to the parts store I expected the guy there to at least be slightly more knowledgeable than the girl, but here's my transaction:
ME: "I need eight autolite 764 spark plugs, please."
HIM: "Ummm, ok. What year?"
ME: (I decide it's best to let him have his routine, hoping that will get me out of there faster) "'95, Ford, Mustang GT"
HIM: "What engine?"
ME: "302"
HIM: "V6?"
ME: "V8" (with a really discusted look on my face by this point)
HIM: "All I show here are the platinums, would that be ok?"
ME: "I'd prefer the copper ones, mind checking to see if you have any?"
HIM: (after finding the box directly behind the counter) "Do these look right?"
ME: "That's them."
HIM: "So, just four or do you need six?"
ME: "Eight"
Then he checked me out and I left wondering how I ever thought that those guys knew anything about cars.