From High Gloss Software:
Sound Grenade for iPhone gives you instant crown control. That party get a little bit out of control. Sound Grenade is the answer. Plug your iPod touch or iPhone into some speakers and crank up the volume. Sound Grenade generates a really, really annoying, nauseating, and headache producing high pitched sound.
What's new in this version:
Version 2.0.1 fixed an issue with the alarm from stopping.