“Flickr, the online photo-sharing Web site, is a good case study
on the benefits of open source. The technology that powers Flickr
is a catalog of open source tools: Red Hat Linux, the Apache Web
server, MySQL databases, PHP, Perl, Smarty templates, Postfix mail
gateways, and even ImageMagick to handle the image
manipulation.“Flickr is a massive collection of digital photographs from
individuals all over the world, linked together by user-to-user
relationships like ‘friends and family’ or interest groups, and by
content-based associations like keyword tags and
collections…”