Google is now hosting the archive of images from LIFE Magazine. This archive would be great for historical research and is also fun to browse. Many of the images included were never even published in LIFE--they are available here for the first time.
You can search only this archive from the regular Google image search by adding "source:life" at the end of the search, for example: coffee source:life
Many of them are very high-resolution, although their copyright extends only to personal use.
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