This Raspberry Pi project creates a floating image using a 150-year-old technique, and I love it
Oldie but a goodie.

Rarely do we see any Raspberry Pi projects that combine new tech with the old. And by old, we mean really old—think stuff people were doing in the 1800s. This cool project is the result of using a Raspberry Pi to perform a miniature version of a classic illusion, and it still looks fab this side of the 21st century.