I think the experiment you refer to is a demonstration of black surfaces and heat reflection not photon energy/mass but I could be wrong..was once.......
You know the experiment, but it is not about heat, but rather a demonstration that light has momentum (and therefor mass). One side of the vanes is black to absorb photons, and the other is silver to reflect them. Shine a light on it and the device spins. I can't find one online though. I remember seeing them in the ads in the back of "Boy's Life."