This guide is huge and its easy to miss the hidden gems. I will try to uncover some of them...
Reference Hub: This section contains a ton of goodies
- Support Engineers use keywords when they create Knowledge based articles, you can include these keywords to narrow down your search, I provided few keywords (such as kbAspNet etc) that you can combine in your search at http://support.microsoft.com
- A Collection of must-read articles
- Sometime back, we started create ROADMAP Kb (knowledge base articles); several support teams with MS started adopting them, check them out under 'Roadmaps and Overviews' section (this is not a comprehesive list). If you or your friend is new to a subject, these roadmaps can help

How Does it work?
- Not may readers may realize that these page contains several internals never documented before.
- Checkout the section 'The Anatomy of a web Request', this contains how the security comes into picture at various stages of the web request

ASP.NET Identity Matrix
This can save you lot of time during troubleshooting or understanding the effect of various settings. There are so many knobs and switches that you can easily get confused/lost. We provide you a list of combinations and the results in an easy consumable form. This also acts as reference, for example, if you are seeing a certain 'Resultant identity' instead of the one that you expect, you know what settings to look for