Randomly from Wiki, an entry on the "heavy metal umlaut":
The heavy metal umlaut, or "rock dots", is an umlaut over letters in the name of a heavy metal band, such as Mötley Crüe or Motörhead. The use of umlauts and other diacritics with a blackletter style typeface is a form of foreign branding intended to give a band's logo a Teutonic quality. It is a form of marketing that evokes stereotypes of boldness and strength commonly attributed to peoples such as the Vikings; author Reebee Garofalo has attributed its use to a desire for a "Gothic horror" feel.[1] The heavy metal umlaut is never referred to by the term diaeresis in this usage, nor is it generally intended to affect the pronunciation of the band's name.
