The film industry quickly discovered that vibrantly coloured posters were an easy way to sell their pictures. Today, posters are produced for most major films, and the collecting of movie posters has become a major hobby. The record price for a poster was set on November 15, 2005 when US$690,000 was paid for a poster of Fritz Lang 's 1927 film Metropolis from the Reel Poster Gallery in London.  Other early horror and science fiction posters are known to bring tremendous prices as well, with an example from The Mummy realizing $452,000 in a 1997 Sotheby's auction,  and posters from both The Black Cat and Bride of Frankenstein selling for $334,600 in various Heritage Auctions.  The 1931 Frankenstein 6-sheet poster, of which only 1 copy is known to exist, is considered to be the most valuable film poster in the world.