Music is the language of but unfortunately not everyone communicates in key. For those unfortunate few who like to sing but are constantly yelled at to shut the hell up, there’s the Noiseless KaraOK for iPhone or iPad.
A muzzle shaped device (which looks like a toilet bowl plunger to me) is placed over your face and you sing away into this. Apparently, you install software in the iPad or iPod and it will create an “isolate environment” to capture the sound into what they call the mute cup. What is an isolated environment? Beats me.
Costing only $50 it’s a steal for something that allows you the joy of singing with the comfort of not having anyone hear you, as long as you don’t mind singing into a mini-sizes toilet bowl plunger. Might have a good market with parents of teenagers who dream of being superstar singers. Source.