On Instructables, Schmidtn posted how-to instructions for his Fart Operated Random Channel TV Remote.
My Pops really enjoys two things; 1) channel surfing and 2) farting.
So one day I was over at Hackaday and read about a guy who used his Arduino to turn a TV on and off with one of those brainwave reading headsets. Then later on that same day I was here at Instructables and a fellow had made an office chair that twitters every time he farted. So, I got to thinking and decided to mash those two hacks into one remote that changes the TV to a random channel every time he tutes!
Plus, if you throw it in a plastic enclosure and hide it between the couch cushions; you've got a purdy dang good prank!