The Ray Harryhausen 1981 stop-motion film about Perseus and Andromeda, Clash of the Titans, is being remade, with the new version due out in March 2010. The trailer for the original can be seen below, and of course there are various excerpts on YouTube.
Ingres's painting shown above was painted around about 1819. It is now in a private collection. (used under creative commons licence, courtesy of www.jeanaugustedominiqueingres.org)
In 1840 Theodore Chasseriau produced the painting above, which is now in Paris's Louvre. (public domain picture from commons.wikimedia.org)
Eugene Delacroix's Andromeda was painted in 1852. It is now in Houston's Museum of Fine Arts but does not appear to be on their website. (used under creative commons licence, courtesy of www.eugenedelacroix.org)
Two artists painted Andromeda in 1869. The upper picture is by Gustave Dore. I haven't been able to find out its present whereabouts, so I assume it's probably in a private collection somewhere. The lower picture is by Edward Poynter and is now in London's Tate Britain. (both pictures are in the public domain and come from commons.wikimedia.org)
Around the same time Gustave Moreau produced the above picture, which is now in the Bristol City Gallery, but not on their website. (public domain picture from www.the-athenaeum.org))
Lord Frederic Leighton's picture dates to 1891 and is now in Liverpool's Walker Art Gallery. (public domain picture from www.museumsyndicate.com)
We continue our exploration of the theme of Perseus and Andromeda, moving into the 18th century with a picture painted in 1723 by François Lemoyne and now in London's The Wallace Collection. A few years later in 1727 Charles-Antoine Coypel also painted Perseus Rescuing Andromeda, which is now in Paris's Louvre. It is not on the Louvre's website, but can be seen in the Joconde database of artworks belonging to the French government. (wikicommons starmap by Roberto Mura used under creative commons licence)
In 1726, Cardinal Pietro Ottoboni returned to Venice from political exile. In honour of the occasion a serenata called Andromeda Liberata was commissioned and performed only to languish thereafter till it was rediscovered in 2002. It is a matter of some musicological dispute whether the serenata was composed by one musician or several, but it is certain that one of the arias, Sovvente il sole, was written by Antonio Vivaldi. The above YouTube extract has the finale from a 2006 performance in Cremona. The New York Times has a background piece to the manuscript's discovery.
In 1730, Tiepolo painted a picture now in New York's Frick Collection, as a study for a ceiling fresco now lost due to WWII bombing.
Anton Raphael Mengs produced the above picture in 1774-1777. It is now in St. Petersburg's State Hermitage. (public domain picture from wikicommons)
Lastly, in 1787 Michael Haydn (brother of the more famous Joseph) wrote an opera, "Andromeda und Perseus", an aria from which can be heard in the YouTube video embedded above.