This site is an expanded and significantly upgraded version of the Flickr Commons based tool I wrote several years ago. As well as a major design/UX overhaul, it now includes data from further providers such as those available through Europeana, and also the Imperial War Museum. I'd welcome further suggestions as the harvesting tool and database are easily extendable.
The data has been harvested from providers using some custom php scripts to query respective APIs based on dates. Data is harmonised and stored in a local mySql database.
The code is openly licensed so please feel free to copy, modify, distribute as you please. It will be shared on Github shortly!