“Views of the Past” is a digital form of a historic monument.
Downloadable from a website, there was an instruction on how to hack old cellphones* and turn them into a digital-monument-device, which is placed in public space. When people with bluetooth enabled mobile phones pass the device, they receive a photo on their phone. The photo is a selected from a flickr-pool of photos showing the location where the device is placed at a past moment.
*Nokia phones, code written with Python for S60.