This project gives you access to the code for upcoming releases that the ASP.NET team is working on, starting with the ASP.NET MVC Framework.

BlogEngine.NET is a full featured blog engine targeted at .NET developers. It is light weight and very simple to modify and extend.

I started this project as a way of learning C# 3.0, LINQ to SQL and ASP.NET 3.5. Right now it is deployed on my personal website http://sietch.net and I dare say it is working pretty well. I believe it has some potential to become usable by other people. It is supposed to be used as a system for personal websites and blogs.

BlueSky Framework makes it easier for .NET developers to develop ASP.NET MVC application.

Web library of reusable components and classes for ASP.NET, Silverlight and WPF Projects, containing image thumbnailers, helpers, behaviors, controls...

.NET library which enables minification, compression, combination, and caching of JavaScript and CSS resources for ASP.NET and ASP.NET MVC web applications. Simply put, it helps your applications rank better with YSlow and PageSpeed.

DataJuggler Controls consists of a series of C# projects containing Web Controls, Windows Controls and WPF controls to make data entry forms easier.

DNN® is the leading open source web content management platform (CMS) in the Microsoft ecosystem.

umlungu's EngineX Web Framework

Fiddler bulk URL extends Fiddler2’s existing UrlReplace command with a few new features like multiple search/replace items, UI, load and save commands, extended command line interface and a few other tricks.

This project provides an object model for building HealthVault-connected applications with ASP.NET MVC

JaernCloud is a domain specific language for web apps. It uses a hierarchical type system called Closure Unified Documents to unify HTML, CSS and data transformations on the server-side into a single coherent programming language. Written in C# with the Dynamic Language Runtime.

JsMapper creates Javascript MVVM-Code (support for Backbone and KnockoutJs atm) from your (Domain-) Classes with support of DataAnnotations

A web based file manager for your website. FTP does not do a good job in managing your website files? This is a better alternative, experience the demo and see.

Mefisto.NET CMS is a project of CMS, developed in ASP.NET MVC4, supporting modularity via MEF, and database access via ORM-Micro (github), a self-made solution.

Morphfolia is a CMS and web application framework (for the typical Microsoft ASP.NET stack), designed to work in a hosted environment. It's been in development for the last 4 years, and is now available on CodePlex. For more info see its offcial site: www.morphological.geek.nz

This project adds additional functionality on top of the MVC Framework. It is written in C#. Founded by Eric Hexter and Jeffrey Palermo.

Class library to create dynamic forms in ASP.NET MVC.

Chat plugin written in MVC 1.0 and jquery using SQL Server for MVC applications

The Open Source ASP.NET MVC Project that runs http://www.nerddinner.com and helps nerds and computer people plan get-togethers.