I made these GLaDOS cores for my friend's cosplay back in October. I was going through my camera and found these so I decided to throw them up. The eyes of the cores glow in the dark a little.
Start with styrofoam balls (your choice of size), add a layer Mold Magic, sculpt it with an exact-o knife, bend some floral wire into its shape, put some more Mold Magic on the wire, paint 16 times to get the designs right, (paint glow-in-the-dark paint or Mod Podge on eye before making the pupil is optional) use stray-on sealer to keep paint from fading/melting/make it look like shiny metal.
Does that help?