Exciting, Happy News
...because we can all use a break from the other kind, right?
The Metropolitan Museum of Art has made available 375,000 images of art, to use as you see fit. 100% without restriction. Public domain. CC-0.
You can explore it here: http://www.metmuseum.org/art/collection
I choose to think of this action as a finger in the eye or President Pumpkin, somehow. But maybe that's just me.