Top 20 NuGet ASP.NET Packages

Lightweight mini-profiler, designed for ASP.NET Core MVC (*not* System.Web) websites
A quickstart package to quickly setup a project as a simple FubuMVC application with StructureMap as the IoC container and Razor as the view engine
AngleSharp is the ultimate angle brackets parser library. It parses HTML5, CSS3, and XML to construct a DOM based on the official W3C specification.
Provides App Service management (Fluent) capabilities for Microsoft Azure.
Adds Cofoundry features to a website, including access to content, pages and media, but excluding any content administration. To add content administration use the Cofoundry.Admin package.
Adds the Cofoundry admin panel to a website.
Amazon Web Services .NET Standard Extentions
Nuget Package for Ingeniux InSite Search V2
Plug-In containing extensions for ASP.NET core.
Exceptionless client for ASP.NET Core. Exceptionless is a cloud based error reporting service that sends your exceptions to https://exceptionless.com and provides aggregated views and analytics.
High-Performance image processing pipeline for .NET. Implements best-of-breed algorithms, linear light processing, and sharpening for the best image resizing quality available. Speed, efficiency, and image quality are unmatched by anything else on the .NET platform.
Kentico Cloud Delivery SDK
ExchangeSharp is a C# API for working with various cryptocurrency exchanges. Web sockets are also supported for some exchanges.
Abp.Web.Common
Abp.Castle.Log4Net
Abp.Zero.Common
Kartris is a free, open source cart system optimized for performance and capable of handling 1,000,000+ SKUs out of the box
Deprecated. Use the strong named ServiceStack.Razor package instead.
NWebsec is an easy to use security library for ASP.NET applications. With a few lines of config it lets you set important security headers, detect potentially dangerous redirects, control cache headers, and remove version headers. See project website for documentation.
dotNetRDF is a RDF, SPARQL and Semantic Web API for .Net. It provides simple but powerfully extensible APIs for this and integrates with a variety of popular triple stores.