What is "cthugha"

Cthugha is a fictional deity in the Cthulhu Mythos genre of horror fiction, the creation of August Derleth. He first appeared in Derleth's short story "The House on Curwen Street" (1944).

Cthugha is a music visualization computer program. It was written in the mid-90's by Kevin "Zaph" Burfitt, originally for the PC, and was later ported to other platforms. It was freely distributed.