Top 20 NuGet asp.net Packages

Fast, extensible, intuitive and easy-to-use C# portable library providing fluent APIs for argument validation. Gives everything you need to implement defensive programming in your .NET application
PostcodeNlApi provides an API to directly talk with the Postcode.nl API through the REST endpoint offered into your .NET (web)applications.
SeoPack is a library packed with lots of SEO goodness for ASP.Net MVC projects.
a re-useable implementation of the metaweblog api for asp.net core
Requires that all methods of contollers should return Task<T>
Enables ASP to read content files (e.g. .css, .js, .aspx) stored as embedded resources in referenced assemblies. This core package contains only an assembly, see also EmbeddedResourceVirtualPathProvider with bootstrap code for seamless integration into your app.
thewall9 CMS Libraries.
Deprecated, see: https://www.nuget.org/packages/SpecFlow.NetCore
ASP.NET Core tag helpers for Subresource Integrity (SRI), Referrer meta tags, OpenGraph (Facebook) and Twitter social network meta tags.
C# typed routing library for ASP.NET Core
Huge dictionary of file extensions to mime types
CRUD extension methods for Dapper
A sample MVC 3 application which demonstrates the features and usage of the 'Elastic.Routing' library.
A powerful string expansion library for .NET you never knew you always wanted. - Use for token-based string templating passing in a model for property replacement - 4 token formats to pick from (MvcRoute-style, Razor-style, NAnt-style or MSBuild-style) - Use as a more readable alternative to string...
Glimpse plugin for Fluent Security.
Adds EditorTemplates for the new html5 input types (including email, tel, and url) to Mvc 3 projects. For example, Html.EditorFor(a=>a.Email) can now generate an html5 input type='email'.
MVC Turbine blade for NServiceBus. Allows the easy integration of NServiceBus into any MVC Turbine enabled application.
ASP.Net MVC library for Ajax, Hijax, and reverse-Ajax (Comet)
WebBackgrounder.EntityFramework is an implementation of the IJobCoordinator for WebBackgrounder that uses a Database (via EF Code First) as the synchronization mechanism (aka a mutex) for coordinating jobs.
A core package to create an internationalization-ready web application