We got a Toshiba Satellite M series laptop in that was making “funny fan noises”.  I took it apart, and sure enough there was a small piece of plastic (perhaps from original assembly) that was roaming around in the case and could work it’s way into the fan area.  When I removed the heat-sink to freshen up the thermal past while I was in there, things got strange.  As you can see in the photos (and dramatized video) below, there was actually a barcode sticker ON the CPU.  I wiped off the paste and you can see it was actually between the heat-sink and cpu likely not helping the cooling process very much.  No biggie, I cleaned it up, applied new paste and put it back together.