This cute little device suction-cups to your window, soaking in sunlight and shooting it out through a hanging prism, giving you (presumably) larger or more vibrant rainbows than you’d get with just sunlight alone. It’s completely useless and obviously a mechanism of the Gay Conspiracy, but I want one pretty badly. Unfortunately, besides this bit on SorobanGeeks, I have no idea where one would purchase such a trifle. (And yes, it’s supposed to hang with the prisms down, but I didn’t want to cram it in).
RainbowMaker [SorobanGeeks]
Update: Or get it at MoMA! Or Amazon! Or WowCoolStuff! (Thanks, Google and Randy and Everybody!)