nd experiencing the event either directly or indirectly including a NASA site. 4 This is an example of a contemporary web cast of the event Tokyo, Mar 25 2006: The national astronomical observatory of Japan and other organisations held an event to webcast a total solar eclipse from Africa and Central Asia when it occurred on Wednesday evening Japan time. The event titled "Eclipse Cafe 2006" was the first of its kind organized by the observatory. Participants viewed live images of the solar eclipse webcast at eight astronomical observatories and science museums across Japan, including Rikubetsu astronomical observatory in Hokkaido and Kazuaki Iwasaki space art gallery in Shizuoka prefecture. Of the eight locations, participants in Hiroshima and Wakayama prefectures had opportunities to ask questions to astronomical researchers in Turkey using a teleconferencing system. The webcasting service was offered with webcast images of solar eclipses in the past. On Wednesday, the images were transmitted from Egypt, Turkey and Libya. The solar eclipse was first observed in Libya at around 7:10 pm local time and lasted four minutes, which is relatively long for a solar eclipse.' Similarity processing algorithms would automatically capture these spatial (where), temporal (when and for how long) and social (who) relationships and create future potential engagement and revenue opportunities from a discrete but significant special interest group. In the case of Big Ben, it is self-evident that there are potentially millions of spatial, temporal and socially linked images, memories and 'advice tags' available to share that can be automatically identified. 10.8 Sharing Algorithms So automated sharing algorithms can be built on automated inference algorithms and automated similarity algorithms. Sharing algorithms are based on an assumed common interest that may include a spatial common interest (same place), temporal common interest (previous, present or possible future common interest) and a social common interest. Most of us are 