Know Your Network, Lesson 4: Access Your Home Computers from Anywhere. LH is often about how to get things done quickly, not how to do it securely.
Sometimes there's a difference, but I agree, in this case running VNC outside any sort of tunnel is a BAD IDEA. Allowing unencrypted VNC access from the internet is a noob mistake. Gee Mom, look what I did! Addressing the Service Provider Transition to IPv6 - Part 1 of 4: The Changed Landscape. Turn Your Old Router into a Range-Boosting Wi-Fi Repeater - Lifehacker.