Christmas in R'lyeh
from a nice collection of Cthulhu Circus Toons.
More Cthulhu fun here.
Other classical cephalopods here (via Pharyngula).
And from a while back but still classic are Tales of Plush Cthulhu, and the Chick Tract parody Who will be eaten first?
And then there is the enemy within.
UPDATE: Put the x back in xmas with plush Cthulhu slippers! (via Boing Boing)