A collaborative website allows users to tag virtual spaces with images from the past.
Historypin, created by the social movement We Are What We Do, who are partners with Google, is a virtual time machine that allows users to take a peek at what the world looked like way back when. The website, which launched in London in June 2010 uses Google Maps and Street View tech and hopes to become the largest user-generated archive of historical images.
From the site:
Historypin asks the public to dig out, upload and pin their own old photos, as well as the stories behind them, onto the Historypin map. Uniquely, Historypin lets you layer old images onto modern Street View scenes, giving a series of peaks into the past.