Mindi made a Steampunk GLaDOS Masquerade Mask out of InstaMorph and a bunch of other parts.
“My steampunk GLaDOS cosplay has gone through several revisions. The woes of a (semi) original character design! Changes to outfit style and changes to how I approach the mask. The mask has been the toughest part, as this is the most identifiable piece to my outfit. I had initially spent hours on an actual mask made of our craft foam and Elmer’s glue. I wasn’t 100% satisfied with it so I took to coating it in Dimensional Mod Podge. Which gave it more of a plastic finish, but since this project wasn’t flat, it started running, leaving very visible streaks. Still unhappy, on a late night whim, I purchased a container of InstaMorph online.”
She heated up her InstaMorph and then pressed it out into a sheet using a glass backing dish and a glass bottle (which InstaMorph definitely won’t stick to). After that, she cut out the hole for the eye, smoothing it all out, then added the decorations to achieve the final look. Obviously there was a lot more to it, and she she has a great set of detailed instructions, as well as more pictures, over on her blog that explain in detail how she did this: http://hyperionkp.com/blog/?p=2841