The severed, animated, flopping zombie appendage is a staple of horror films, and these zombie-mouth cupcakes look like someone has decorated an amuse-bouche with a bouche coupé.
As with this morning's brain cake, the true lurking horror of these is that all the nifty 3D stuff is accomplished by means of fondant, which, while technically edible, isn't very nice.
In Zombie Russia, cupcakes bite you!
Zombie Mouth Cupcake [Semadarg/Instructables]
(via Geeks Are Sexy)