Some of the Technical Blogs to learn something you don't know
Ubuntu Server Guide - How to's
Nagios Core
Geekpeek.net - Open Source tutorial
i-Secure News and Security tutorial
The Tech tutorial
Unixmen - For all *nix
Technology UK - Communication - Electronics - Networking
Datacenterdude - All related datacenter activities
A virtualization and Data center Blog
A UNIX Admin School
Redhat Linux Blog - How to's
Netapp and Powershell Guides - Cosonok's It blog
SAN Netapp and VMWARE Blog - andrian horja
Sysadmin Tutorials
Senthil IT infrastructure Site for Unix and SAN
Linux FAQ's -
Techniques and web technology blog
Server World
Servernoobs
Question Defense
Monitoring - Exchange Server
A Collection KB's
Unix Interview Questions
Linux Server Guide - Open Source Guide
IT Blog Specializing in Networking, virtualization and Open Source