AKA MSDN. MicrosoftCorporation's subscription-based service for developers.
MicroSoftDeveloperNetwork includes two main features:
MicroSoftDeveloperNetwork is almost always bundled with other products, typically various OperatingSystems and VisualStudio packages.
See: http://msdn.microsoft.com/
AddToMe: Could a current MSDN user check ove this, since I've not actaully used MSDN is a couple of years.
3 pages link to MicroSoftDeveloperNetwork: