I really like the Community Solutions articles in the Microsoft KnowledgeBase, written by Microsoft Most Valuable Professionals (MVP's). They are insightful, at times slightly ironic and sarcastic and sometimes they make me laugh and almost wet my pants. You recognize these articles immediately when you look at the Knowledge Base article number: they all start with 555.
There are a lot of KnowledgeBase articles that I believe to be magnificent:
Common Mistake articles
How to ask a question
How to move Software Update Services (SUS) content from one drive to other drive locally
How to enable and disable Shutdown Event Tracker
How to export Root Certification Authority Certificate
How to move a certificate authority to a new server running on a domain controller.
How to enumerate locked out user accounts using Saved Queries
How to manually create Default Domain GPOs
How to force adding of Domain Admin Group to Local Admin Group
How to leverage Group Policies with WMI Filters
How to migrate objects from one domain to another in the same forest
How to enable Windows 9x client to use home directory in Windows 2000/2003 domain environment
How to upgrade Small Business Server Domain Environment to regular Windows 2003 Domain
How to Improve Windows 2003 File Server Performance
How to configure Windows Server 2003 SP1 firewall for a Domain Controller
How to remove completely orphaned Domain Controller
Check them out!