Simple Noise Maker Circuit

I need a very simple 'NOISE MAKER' circuit design. I say 'very simple' because a simple electronic humm sound is all I really need to hear. There are articles on the net describing how to make simple noise. Two examples below: 1. [login to view URL] Building a Noise Maker with Bare Paint and a 555 timer Note: For what I need, everything must fit onto a single bread board however! 2. [login to view URL] Instructions: Build an Electronic Noise Maker Things You'll Need: One 555 integrated circuit One 500 microfarad capacitor Two 1 ohm resistors Read more: [login to view URL] Note that I ultimately need a 3.5mm audio jack to hear the noise through a headset and it's essential that I be able to hear the noise through a headset **WITHOUT it making any external sound.** That's why I don't buy a $1 buzzer. Nothing more than a few cheap components should be required for this design.