This is the brain-slug wig I made for Doc to wear this Halloween (I picniked in the Frankenstein mask to protect Doc's anonymity). Doc was really pleased with the whole thing, and has already said that this is going to be his costume for years to come.
The wig itself was five bucks from KMart, and I think it's supposed to be an Elvis wig, but really it was just a curly mop. I definitely couldn't have made anything better, and, a couple of times at the Ghost Train, I forgot Doc was wearing it and lost him for a minute or two.
Obviously the crocheted brain-slug really added that touch of verisimilitude that a cheap wig needs to be convincing.