I found a nice scan of a Picasso sculpture, ''Head of a woman''. I edited it to be 3D printable by cutting a flat base and deleting noise, filling holes, sculpting/smoothing a bit and scaling the model up.
The original scan can be found here: http://www.123dapp.com/catch/Picasso-I/4604821
The author marked this model as their own original creation. Imported from Thingiverse.