Rutgers University demonstration specialist, Demo a Day co-author, and That Physics Show star, Dave Maiullo, presented many demonstrations, as he does. With trademark Maiullo panache, of course. One of them was the use of Ikea's Ledberg color-changing LED light strip in conjunction with diffraction ("rainbow") glasses. The LEDs in the strip act as nice point-like sources, a controller allows for variation of the emitted color, and the diffraction gratings produce a nice spectrum that changes in correspondence with the LEDs.
Here's Dave's presentation to a group of physics teachers (Session CM: 30 Demos in 60 Minutes). [Note: this is operationally a family affair as many folks in the room know each other and the demonstrators; so the atmosphere is familiar and casual.] As an attendee, I did my best to capture as much of the session as I could. I did better with some demos than I did with others. My rainbow glasses were secured beyond my ability to deploy them while recording the demo. That didn't stop me from trying!
I managed to make an effort to hold the glasses in front of my big camera during the official demo show. A bit slapdash; I'm delighted it worked as well as it did to show the spectra of the LEDs off to the right.