You know, when nobody but my wife and an empty bottle are looking, I'll sing a little Rock Band. This lady is equally timid on the m.i.c., but has a cunning alternative: play the flute.
Yes, as with SingStar, Rock Band can't understand your actual words while singing. It just picks up the pitch and tone and runs with it. So while singing can, and normally does get the job done, if you can play the flute, you can get the job done via other means.