This topic is pretty self-explanitory: what is your favorite painting, or piece of contemporary artwork? My favorite, interesting piece of artwork is The Scream by Edvard Munch. And facts about different pieces of artwork? Like in the Washington Crossing the Delaware painting, it shows a bridge that wasn't even there when he crossed the Delaware.
While I can't think of a specific one, many of John Howe's works help inspire me when I'm in an artistic block.
But for an example, his painting Nighteyes and Buckkeep really shows the rich beautiful colors and the fantastical imagery that gets my artistic juices flowing.