The Museum of London superimposes archive photos and paintings of London on modern photographs.
I've got goosebumps. It's like having all the stories and novels that I've written which have more than one time in them, come to life...
http://www.dailymail.co.uk/news/article-2351509/Unique-phone-app-shows-photographs-iconic-London-locations-overlaid-historical-views-exact-spots.html