It may not be exactly the same as standing in front of masterpiece paintings by the Old Masters, but if you can't make the plane trip to Madrid, Spain, it's still pretty darn neat.
Google just launched a Google Earth feature that lets you view select paintings from The Prado Museum in astonishing details:
The Prado Museum has become the first art gallery in the world to provide access to and navigation of its collection in Google Earth. Using Google Earth, art historians, students and tourists everywhere can zoom in on and explore the finer details of the artist's brushwork that can be easily missed at first glance.
The paintings have been photographed in very high resolution and contain as many as 14,000 million pixels (14 gigapixels). With this high level resolution you are able to see fine details such as the tiny bee on a flower in The Three Graces (Las Tres Gracias), delicate tears on the faces of the figures in The Descent from the Cross (El Descendimiento) and complex figures in The Garden of Earthly Delights (El Jardin de las Delicias)