A new online Wayback Machine focused on historic images of the city has launched. 502Louisville is an ongoing exhibition of the history of Louisville through photographs. Each post includes at least one vintage photo and some historic information about the site. Some posts document buildings that no longer exist, while others show how city blocks have grown over time.One of the site's cooler features is Mashup Monday. Start the week with a Louisville location that switches back and forth between an historical photo and a contemporary view, like this view of the Douglass Loop that shows the corner's evolution from signage-heavy streetcar stop (1936) to tree-lined intersection (now). Another feature is STASH (Some Things Are Still The Same), photos that show buildings and outdoor scenes that haven't really changed much over the last century. The site makes heavy use of the University of Louisville's photographic archives, but is actively requesting community involvement. If you have old photos of Louisville, contact the curators. They're also looking for guest writers, so if you have cool old photos and/or stories about Louisville's history, let them know.