SQL Server Central
SQL Server articles, scripts, and discussion groups.

MSDN Online - SQL Server Developer Center
The one-stop for developer information from the source about Microsoft SQL Server.

Narayana Vyas Kondreddi's SQL Server Website
This site features SQL Server administration, programming and security best practices.

sqlServer.co.nz
SQL Server resource site that includes articles, book reviews, product reviews, news and links. By Tony Bain.

Microsoft Data Warehousing Alliance Members
List of DWA members and related information that is maintained by Microsoft.

SQL Server Superexpert
Comprehensive SQL Server resource that contains SQL Server FAQs, software, jobs database, and links to articles, books, and software.

Tek-Tips Forums - Microsoft SQL Server
Support forums and mutual help system for computer professionals. Selling and recruiting forbidden.

SQL-Server-Performance.Com
Performance tuning and optimization articles and tips on Microsoft SQL Server, including versions 6.5, 7.0, and 2000.

SQL Team
News, technical articles, and your SQL Server questions answered free by experts.

SQL Security
News, FAQs, and scripts focusing on Microsoft SQL Server security.

Microsoft SQL Server
The official information site about the family of products. By Microsoft.

Devdex.com
An index site of SQL Server-related resources. By Developersdex.

About.com on Microsoft SQL Server
Provides articles, links, forum discussions and a chat room.

T-SQL solutions
News, forums, tips and articles focused on Tansact SQL language.

MSSQLCity.Com
SQL Server articles, FAQ, scripts, tips and free test exams.

eEye Digital Security: SQL Worm Analysis
Technical description of the SQL worm (AKA: Spida, Digispid.B.Worm) and a free scanner.

DevASP.Net Directory of SQL Resources
A directory of SQL resources, articles, training material, samples, tutorials, scripts, applications, books, software and sample chapters arranged by category.

Novick Software
Well written articles, code samples, tips and tricks, book reviews; consultancy.

SVEK Computing SQL Server Site
Tip library offering suggestions on a variety of data operations and administrative topics.

XPrime Database Performance Cluster
Hardware/Software package that uses clustering technology and main memory database to increase performance.

SqlJunkies.com
Developers community site with blogs, forums, news, and events.

SQL Server Comparison Tool
Analyze, compare and document structure of tables, procedures, functions, views, triggers and relationships, compare data stored in tables, generate detailed reports.

DBAzine
Provides tips and articles helpful in everyday SQL server usage.