To scream without ever opening you mouth, there's the 'UURGHHH' jewelry line from Tatty Devine.
This differentl collection of monster moan-inspired necklaces and accessories are all part of the Hoxton Street Monster Supplies store, which specializes in just that: monster-like accessories and goodies. Each necklace features a different ghastly groan including "uurghhh," "aarghhh" and "grrr." According to Devine, the pieces are "crafted from sustainably sourced human bone" and "from recently-petrified forests", which makes the creations even ghastlier than they appear. Each piece is handmade in London in Devine's underground studio with proceeds of the collection going to help fund writing workshops for teens and young adults in East London.
The limited edition line can be found on Devine's personal site along with some of her other kitschy designs. If you're eyeing one of these items in particular, be sure to grab it fast before another creature beats you to it.