...two loud-ass horns.
in the lineup for gas yesterday there were 2 cars in front of me in one pump lineup (there was a gas war).
i picked the lame duck pump as the guy at the pump was fairly confused by the pay-at-the-pump debit card setup and was taking his time. the car directly in front of me apparently had enough of this and slapped it in reverse and backed up without looking.
luckily my hand was on the horn button (ironically) and i laid it on. filled the whole gas station with lovely loud Dual huge horn sounds for all around to enjoy)
The guy gets out (as i am shaking my head) and says i didn't even see you (thanks captain obvious).
anyway - i'm actually thinking about louder airhorns now. you know - i think they call them train horns.... hmmmm.... i already have the compressor / tank / etc.....