Silk Brain
The more wrinkles you have on your brain, the smarter you are. Having a silk brain is the lack of wrinkles on your brain, denoting extreme stupidity or inebriation.
"Nice move, silk brain."
"What a silk."
"Did you see Matt at the bar last night? He got silky as hell."
"What a silk."
"Did you see Matt at the bar last night? He got silky as hell."