Cthulhu-13
I’m disappointed to find that “Ph'nglui mglw'nafh Cthulhu R'lyeh wgah'nagl fhtagn” doesn’t turn into anything interesting when rot-13ed.
(It becomes “Cu'atyhv ztyj'ansu Pguhyuh E'ylru jtnu'anty sugnta.”
(Perhaps I’ll try to turn Pguhyuh into a catchphrase, the way alt.folklore.urban turned furrfu into a catchphrase.)