Might anyone have an idea what this knocking is?

All of a sudden I am getting a very audible knocking from the rear end after I engage the car in gear and release the clutch and apply tourque to the wheels. The knock increases with momentum but is very inconsistant in it's rhythm. Only when I engage the clutch or drop into neutral does the noise go away. Does this scenerio eliminate the possibility of a CV joint problem? Please tell me it's not the tranny or clutch......actually...it's ok, just give me your best opinions...I'll cry later.
Thank you

sounds like cv joints to me.

http://www.clarks-garage.com/shop-manual/susp-01.htm

that gives some general info plus repair process.

To make you cry: it could also be your ring and pinion in the tranny.

Wheel bearings usually make noises during corners.

It's most likely not the clutch though.