Not to get to geek on y'all, but I noticed this on the popular woodworking website and thought it was cool.
All of there articles are indexed by number. You can find "hidden" articles by changing the number in the query string and navigating. For those of you who don't know what a query string is here is the layman definition:
The part of the URL web address after the question mark ?. So, go to an article on the site, go up to your address bar and change the number at the end of the address. You may need to keep trying different numbers, but you'l probably hit one or two.