The whistler at work

Most of us have coworkers that seem to be very inconsiderate, even annoying at times. And sometimes they're not even aware that what they're doing is bothering others already. It's somewhat a tricky situation. I mean, you could tell a person to stop but it might offend him and possibly cause friction between the two of you. If you don't tell him, he wouldn't be aware that he's bothering some people already. Worse if it's your boss. I mean, it's not easy confronting your own boss about it. It's as if whatever option we take, we end up at the losing side.