Exemplo de feed do Flickr:
wget -O - http://api.flickr.com/services/feeds/photos_public.gne |grep 'rel="enclosure"' |perl -lpe 's/^.*href="([^"]*)".*$/1/' |xargs wget -c
Usando Perl para Regxp:
sudo aptitude update && sudo aptitude install perl-doc && man perlre