The Jargon File (version 4.4.7, 29 Dec 2003):

cthulhic
 /kthool'hik/, adj.

    Having the nature of a Cthulhu, the horrific tentacled green monstrosity
    from H.P. Lovecraft's seminal horror fiction. Cthulhu sends dreams that
    drive men mad, feeds on the flesh of screaming victims rent limb from limb,
    and is served by a cult of degenerates. Hackers think this describes large
    proprietary systems such as traditional mainframes, installations of
    SAP and Oracle, or rooms full of Windows servers remarkably well, and the
    adjective is used casually. Compare Shub-Internet and crawling horror.