Two US journalists, Laura Ling and Euna Lee of Current TV, are currently being detained in North Korea. The London Times say that the pair face the "possibility of a show trial and ten years in a notoriously harsh North Korean prison camp."
Mike Knapp, a former Google employee turned entrepreneur has created this Google Maps mashup so that you can show your support for the two journalists. The mashup allows you to join a virtual vigil for the release of Laura and Euna. The vigil is held over Pyongyang, where the pair are being detained, on Google Maps.
To add your support you just need to log in with a Google account, choose an avatar and leave a message of support. Your message will then be added to the other messages of support on the satellite image of Pyongyang on this Google Map.