How to access 375,000 beautiful, copyright-free images from New York’s Metropolitan Museum of Art
"New York’s Metropolitan Museum of Art has released 375,000 images of works from its collection, with no restrictions on what you can do with them. The images, all of art in the US public domain, were previously available online, but with some stipulations about commercial use. You can find them at the digital collection, with “Public Domain Artworks” checked in the left-hand column."