War Time ID Badges
At the onset of World War II, almost every business or manufacturer who did work for the war effort required employee ID badges for permission to enter the premises. These curious photographic objects are collectible examples of a time before the high-tech security, fingerprint and iris scans we have today.
Mark Michaelson, author of the book Least Wanted, has a fabulous photostream on Flickr with hundreds of photographic mugshots, ID badges, and other similar examples of identification. These photo badges, which can occasionally be found at estate sales and antique stores, make a very visual and affordable collection if you want to start looking for them.