I'm always skeptical about the quality of novelty gadget accessories, but I can't argue the aesthetic appeal of the Flash For Diana+, $60.
The flash was inspired by the original '60s design of the all plastic and vintagey Diana Dreamer and Diana F+ cameras, which are famous for bright and lo-fi images. Of course, this modern flash comes with an adapter for any standard hotshoe camera.
The "Diana Plug" attaches directly to the camera and fully syncs the flash. An integrated color flash feature allows you to splash a burst of colored light at your subject and the flash ships with a set of plastic color gels.