I'm a high school science teacher and I've got a nasty cough.

First period I say after a particuarly long series of dry hacks, "Sorry I sound like General Greivous."

Nothing. No reaction. Blank stares.

Curious, the next period I said, "Sorry I sound like Darth Vader." and got a couple small chuckles.

I alternated the rest of the day. Here are the results.

Greivous: 3 periods of total silence.
Vader: Small chuckles, scoff of recognition and twice being told "Darth Vader doesnt' cough."

My students are 14-15 years old of a wide range of ethnicities from the lower to upper-middle classes. It's not exactly a scientific study, but it gives me some hope for the future.