I really wish the USC and LAPL collections were geo-tagged. When you put together a whole collection of photos from the same general area like this^^^ it really gives one a good perspective of what they are looking at, and how the city developed over time. A good example of this is on Flikr on Vokoban's page. This is the guy who meticulously mapped out the theaters along Main Street
http://www.flickr.com/photos/vokoban/map/