Old Maps Online - Keyword search of more than 120,000 maps by the end of 2012
Archive-It - 1,700 collections, many available to all without a fee
Road 2.0 - Resource of Outdoor Advertising Descriptions - Provided by Duke University Libraries; more than 30,000 digitized images with search/browse capability. Great for projects calling for images from the 1930s through the 1980s
Scirus - A science-specific search engine for grades 6-12. You can search by keyword, refine your search, save and/or e-mail your search results. The focus is on Web sites containing only scientific content.