You can spend a fortune hardening the perimeter and still get walked through the front door by someone who simply asked nicely. The uncomfortable truth of security is that the strongest link in most organizations is the technology, and the weakest is the person reading their email at the end of a long day. Attackers know this, which is why so many real intrusions don't start with a clever exploit. They start with a message. An email that looks like it's from a colleague, a vendor, or the help...