# Log in to the server. This only needs to be done once.
wget --save-cookies cookies.txt \
--keep-session-cookies \
--post-data 'user=foo&password=bar' \
--delete-after \
http://server.com/auth.php
# Now grab the page or pages we care about.
wget --load-cookies cookies.txt \
http://server.com/interesting/article.php