Amit Sood is the head of Art Project, a Google initiative to bring the world's art museums onto the web. Visit it at googleartproject.com.
Library of Congress Digital Collections -- Created by the Library of Congress, the Digital Collections website is a gateway to rich primary source materials relating to the history and culture of the United States. The site offers millions of digital items from more than 100 historical collections.
Art Images for College Teaching
Google Arts & Culture -- A project that includes images from museums, archives, and other institutions around the world. Create and share your own "collections."
Visual Arts Data Service (VADS) -- A well-designed site with a focus on fashion, craft, 2D design, and contemporary artists working in the United Kingdom and internationally. It is a repository for many special collections in the UK.
Web Gallery of Art