Have you ever noticed that when people use a webcam with a built-in microphone to voice chat the room acoustics and other noises are more noticeable than with a headset or boom mic? This is because the mic is so far from their mouth where voice is strongest compared to the rest of the room. This Instructable (my first) will show you how to add an external mic jack so you can plug a lapel or headset mic into the EyeToy camera (and many other webcams) to be heard more clearly. If you have an EyeToy and still haven't installed it on your computer, see this instructable Turn-a-PS2-EyeToy-Camera-into-a-High-Quality-Webcam.
http://www.instructables.com/id/Give-Your-EyeToy-or-other-Webcam-an-External-Mic/