Top 20 NuGet asynchronous Packages

Provides a Stream.CopyTo overload for reporting the current progress while copying.
Web API exposing the AsTrEAM asynchronous WCF stream service to help setting up a multi-tier architecture.
Adds an asynchronous stream service to a WCF Service Application
Provides Stream.CopyTo overloads for reporting the current relative or absolute progress while copying.
Provides an easy to use asynchronous HTTPS and HTTP that is ultra light-weight, portable, and fast for usage with micro-services. Intended to replace heavy-weight resource hungry and wasting frameworks with something that is dependable, simple to maintain, and fast.
Automatically login a bunch of accounts to PlayerIO with extreme haste.
Asynchronous Log4Net appenders and forwarder
Easy way to implement Event-based Asynchronous Pattern in .NET.
Fully asynchronous memcached client that uses consistent hashing to minimise cache loss if a cache server leaves the cluster or if you add a cache server to the cluster. Built in performance counters so you can see how the memcached client is behaving on your machine and how many requests you are ma...
Minimal, lock-free, IAsyncResult implementation for .NET 4.x
Event-based asynchronous http-load testing library.
Http-load testing tool.
Eventing is a library for asynchronous event-driven programming
.NET sockets made easy (Now part of MniakLibs)
.NET Data and Database Extensions
A library that provides simplified threaded and non-threaded execution of SQL statements. It can be used to expose an interface to Microsoft Excel clients, providing threaded, async operations to a single-thread application.
Asyncify-CSharp is an analyzer and codefix that allows you to quickly update your code to use the Task Asynchronous Programming model. This model, introduced in C# 5, adds an intuitive way of handling asynchronous calls within C#. The analyzer allows large codebases to be easily modified to use the ...
A .NET class library that abstracts away the details of asynchronous network programming. http://github.com/chutch1122/SimpleAsyncNetworking http://simpleasyncnet.cameronh.me/
RestSharpHelper Small library helper for RestSharp including rate limit, oauth1 support, helper for async download, usage of JSON.Net as json serializer and some helper method
A library for creating interactive applications using state machines and asynchronous programming.