Vija Celmens “Night Sky #2” / keys

(In 2008, while on view at the Carnegie Museum of Art in Pittsburgh, Celmens’ work was attacked by a museum guard, who scratched the canvas’ surface with his keys.

“I didn’t like the painting,” guard Timur Serebrykov told police when they arrested him. “I’m sorry.”

The painting was restored, although it still bears a faint scar.)