That's a Digital Micromirror Device. A thing I always wanted to see, but never found a projector which was broken enough to be in the trash but yet still working enough to produce an image - until now.
Some other good videos on DLP/DMD:
https://www.youtube.com/watch?v=w1mE2j1axIo
https://www.youtube.com/watch?v=N4aUU3-PKQ4
https://www.youtube.com/watch?v=9nb8mM3uEIc