.Net : main resources, tools and libraries, open source or not, to build entreprise level applications?

Question

As a young professional in .Net, I noticed that there are plenty of .Net application blocks for build an entreprise level application. Still, I could not find a place where all these resources are gathered, as an entry point to .Net development for beginners or professional.

Here is my question. Which application blocks do you use in your entreprise-level application? Please classify your blocks (database access, GUI, testing... add tags to it dammit!), precise if it is open source or not. If your library provides functionnality in several fields (like Microsoft prism), some additional information would be great.

Be specific. No tiny useful block shall be forgotten. Vote up useful and entreprise level libraries, vote down unstable ones. Gotta catch'em all!

Of course if such a place exists, I'd be glad to get its url ;-)

Libraries :

• Microsoft Entreprise Library (Caching, Cryptography, Data Access, Exception Handling, Logging, Policy Injection, Security, Unity ie Dependency Injection, Validation - Open Source) by Robert Harvey
• NHibernate (O/R Mapping, Data Access - Open Source) by g.
• Proj.Net (Spatial Reference and Projection - Open Source) by George

Resources :

• CodePlex (Open Source) by Nifle
• CodeProject (Open Source) by Nifle
• SourceForge (Open Source) by Nifle

Answer 1

There are several places that have open source .Net libraries and applications for you to rummage through.

Here are a few

• CodePlex
• CodeProject
• SourceForge

Answer 2

ProjNET - to deal with projections and spatial data. OpenSource!

Answer 3

The Microsoft Enterprise Library is a collection of reusable software components (application blocks) designed to assist software developers with common enterprise development cross-cutting concerns (such as logging, validation, data access, exception handling, and many others). Application blocks are a type of guidance; they are provided as source code, test cases, and documentation that can be used "as is," extended, or modified by developers to use on complex, enterprise-level line-of-business development projects.

http://msdn.microsoft.com/en-us/library/cc467894.aspx

• The Caching Application Block
• The Cryptography Application Block
• The Data Access Application Block
• The Exception Handling Application Block
• The Logging Application Block
• The Policy Injection Application Block
• The Security Application Block
• The Unity Application Block
• The Validation Application Block

Answer 4

NHibernate for persisting objects to a relational database.