Google just launched a new feature: explore the masterpieces from the Prado museum in Spain (like Velazquez' Las Meninas and a Durer self-portrait). You can view the works in Google Earth and Google Maps. It's so high res you can see the texture of the canvas and globs of paint.
It's stuff like this that makes me realize how much of an art dork I am.
Not exactly illustration but I thought it'd still be appreciated here.