Can anyone suggest a great webcam for a Mac?

I need a freestanding webcam that is plug and play for the Mac platform.

The built in camera does not meet my needs since I need the camera to point in a different direction than the screen. I am using it to demonstrate, and will have it pointed at paper on my desk.

Wish list would be glass lens and low light correction- HD is a must so that what is written will be visible. A mic would be great too.

My budget is roughly $50 but for the right cam I could go higher.

Any suggestions? Again- has to be MAC compatible.

Many Thanks!