John Sullivan’s projector suffered some unplanned damage. The mirror inside the projector that reflects light from the bulb was broken, rendering the unit useless. The mirror was an odd shape, so he cut up a platter from a sacrificial hard drive and made a replacement. If you’re looking for other projects for those old drives, I dug up a few. The hd motor anomemeter is interesting. The brushless motor can be used to generate AC current to calculate the speed.
[Hopefully comments will be back this week. I'll get into the details when it's fixed.]