Rex, I apologize for high jacking your topic but I would like input
from the same group of responders.

Problem: Auto boom boxes. You know. The ones who pull up beside you at
a stop light and rattle the change in your ashtray.

Solution: Just once, OK every time, I would like to hit a switch and
shatter the side glass in his car. Rear, of course, we don't want to
injure anyone.

Assignment: What frequency would have the desired effect and how do I
build it.

I can hear the little pimple faced prick now talking to his buddies,
"Man, I just cranked it up and it blew the window out!"