| A 1924 photograph by artist Man Ray, depicting a woman - the model is Kiki - from behind. She wears a turban and earrings, her head is turned to the left, and she is naked except for some fabric draped around her hips. Most striking on the model, though, are two f-holes positioned on her back in roughly the same position as on a cello.
The piece's title, Le Violon D'Ingres, could be translated from French in two ways. It could simply mean "Ingrid's Violin" - a reference to the stringed instrument shown on the woman's back - or it could be understood as "The Rape of Ingrid" - perhaps a Dadaist reference to the use of women as instruments or objects of pleasure.*
While the model in Man Ray's photograph does not have the marks on her skin - they were added by brush later - the image has become a popular source for actual tattoos.
"Le Violon d'Ingres" is also a Parisian symphony orchestra under the direction of Claude Raymond, and a restaurant near the Eiffel Tower led by chef Christian Constant.
* - It is likely that the phrase Le Violon d'Ingres was used to mean "hobby," and that the picture is modeled after the artwork of painter Jean-Auguste-Dominique Ingres. See the final URL in the notes for more information; LeoDV also provided that detail. Foetus also confirms that my story is pretty much completely made up. I do like it, though.
The restaurant: http://www.leviolondingres.com/
The orchestra: http://perso.cybercable.fr/baicolja/
The photograph: http://www.ocaiw.com/galenug350.htm
More on the photograph: http://www.getty.edu/art/collections/objects/o61240.html
The tattoo may be seen on the backs of lotusFlow and etoile. There is a picture in etoile's homenode. | 
