The big IPv6 experiment
With more than 150 million page impressions per month, heise Online is one of the biggest news sites in Germany. Globally, it is also one of the largest sites now running in dual-stack mode, which means that pages can be accessed via both the conventional IPv4 and via the newer IPv6. The migration brought to light various interesting phenomena.
You don't need to be a genius to debug a pf.conf firewall ruleset, you just need the guts to run tcpdump