filk

filk /filk/ n.,v.  [from SF fandom, where a typo for
   `folk' was adopted as a new word] A popular or folk song with
   lyrics revised or completely new lyrics, intended for humorous
   effect when read, and/or to be sung late at night at SF
   conventions.  There is a flourishing subgenre of these called
   `computer filks', written by hackers and often containing rather
   sophisticated technical humor.  See {double bucky} for an
   example.  Compare {grilf}, {hing} and {newsfroup}.