I just spent two hours browsing around the famous Rijksmuseum in the Netherlands, from the comfort of my home office.
This is one of the best art sites I have ever found, and the very best I've seen when it comes to closeup reproductions of the masterworks.
At this website (
www.rijksmuseum.nl ) you can click the zoom button under the images and feel like you're nose to nose with the most jaw-dropping Rembrandt, Hals and Vermeer portraits, among many others.
You can also take a virtual museum tour, going room to room. Click on the up arrow at the bottom of the window to "turn on hot spots" so you can tell which of the paintings shown on the walls can be enlarged.
Have fun!