I have had my 2008 unibody macbook for sometime now. 3 weeks ago there was a clunking sound in the fan constantly. picture a Ford Model T sound like " dugdugdugdugdug" or something i cant explain the sound. suddenly today it got a ton worse. now sounds like a lawnmower. Here is a video of someones macbook that sounds EXACTLY like mine. http://www.youtube.com/watch?v=K_HE0U6ppWA&feature=related this sound really worries me. i dont have apple care anymore. what should i do?