We really need a Bowel Disruptor in Shadowrun.
I can see it done using magic (think Orgasm...), but tech?
Heh, the Screech sounds (natch) like the perfect starting point. Perhaps allow additional charges to up the damage done when in single target mode (tho if run from a external power source that can turn very very nasty). The nausea effect is a catch-all, so it could be described in the appropriate manner.