From time to time a DM is required, by law, to absolutely scare the crap out of his players. My friend Thurston used this figure of "Demo-Holder" to do just that to us back during our college days.
I don't remember exactly how he came up with the idea, something about the fact that Demogorgon's heads actually competed against each other and already had "gaze" type powers leading to an escalation of horrifying proportions. :-)
The figure is a Minifigs Demogorgon with the heads replaced by Eleven-Eyed Floaters (*cough*beholder*cough*) from Archive.
And here's a "Family Album" shot of Demo-Holder with the Demogorgon figure from Grenadier (left) and the more recent plastic Demogorgon from WotC (right).