Haha--Make a tape-recording of screeching tires and play it through a handlebar-mounted boombox!
I was reluctant to disassemble my good bike in order to mount the spacer-mounted bell; but I have transferred it back to the basic handlebar clamp and I'm going to give it a test today. Maybe people will hear it better than I think.
I don't want to have to be within 10 feet for them to hear me, though. I could just clear my throat for the same affect. It startles people to be that close before they are aware of you.
Perhaps I could disguise the Airzound as a rubber chicken and hang it upside-down from my bars . . .