I just noticed an article in Wired about a potter who is makeing raku ray guns. They're really nice. You can find them at http://blog.wired.com/tableofmalcontents/2007/04/ufo_ray_guns_in.html.
I've been making ray guns for several years and also do them on the wheel, but they're made from procelain and used a clear glaze fired at cone 6. On the first two, I selected primary colors in order to relate to the colors used in cheap, shiny plastic toys. Sometimes I have used underglazes and sometimes overglazes. The first one is named "Molecular Redistributor".
The second is "If Mars Attacks" and has more overglaze treatment, though it is difficult to see the difference. Both "If Mars Attacks" and "Molecular" were exhibited at "Toys Designed by Artists" at the Arkansas Art Center in Little Rock AR and "The Whmsical Clay" show in Beverly, MA a couple of years ago.
The white ray gun, "Ectoid Extractor" , has not been shown anywhere yet. I have a mate to this one still in the studio yet to be assembled. I like the white shiny surface and glass combination.
The darker fourth gun is "Lunar Artifact" and it was included in the Whimsical show at the end of last year.