Restaurant, or home, seating with incorporated acoustic conduction and resonators/soundboards for helping aspiring raspberry blowers celebrate their wind, and improve their technique.
An enhanced restaurant version could have a table based soundboard fed by multiple seats, so that it wouldn't be so
obvious who the culprit was. In addition, simultaneous farting could lead to some fairly artistic 'mixing of colours'.
I'm going to have to leave it to the acousticians to actually figure out the details on this one though. Perhaps specially placed airports on the sitting surface, with specially shaped resonating chambers beneath, etc. etc.?