Need help with masks...

[Dante]

I cosplayed for the first time at Fanime 2k7 and it was the most fun I've had at Fanime.  I'm looking to put even more into it for 2k8.  Ive gotten very interested in mask making and was looking for any and all crafting pointers (i.e. recommended materials, sculpting & painting techniques, etc.)  I seem to remember some sort of liquid latex-style substance that was good for masks, but I do not remember what it's called.  Any input is greatly appreciated, and I'll see you there.