In his Cthulhu Mythos, H. P. Lovecraft includes several snippets of the R'lyehian language, including the "Cthulhu chant":
Ph'nglui mglw'nafh Cthulhu R'lyeh wgah'nagl fhtagn!
We have a vocabulary list available, that gives us a decent taste of the words - for instance, 'ai means speak or call.
Does this bear any resemblance to any natural languages? Do we know the inspiration for the words?