Thought I'd share this since the whole procedure was much easier than I thought it would be... and was also a lot of fun!
My MBP is over 5 years old and had a really annoying fan noise. So I finally decided to take it apart and see if I could fix it. I had read in a few different blogs/forums that people fixed it just by lubricating. I took the laptop apart (relatively easy) then took the right fan out. i noticed the top part of the fan housing was slightly bent downwards, causing the fan blades to touch the bottom of the housing. I bent it back and that fixed the nasty grinding sound, but the fan was still a little noisy. I lubed it up really good with some 3-in-1 and it was completely silent. So silent that I could hear a tiny noise from the left fan, so I took that fan apart and lubed it too. there are a few important things to look for when taking the fans out. The right fan is pretty simple (just untape the wires running over top) but the left fan has a lot more crap around it. There is a ribbon type thing that connects the light sensor to the mother board. The part it connects to can be flipped up and the ribbon slides out. Just remember to reconnect afterwards!
My macbook runs completely silent now! success! And I spent $0 on parts and labour =) I'm going to pick up a 7200rpm 500GB hard drive to replace the 80GB hard drive (big at the time!). I need a new battery too. If I buy both I'll be in around $150, saves me buying a new laptop.
