Top 20 NuGet owin Packages

Asp.Net Owin middleware for SharePoint Add-ins for Asp.Net MVC 5
Google Recaptcha Owin Middleware
A self-hosted slack bot for responding to outgoing webhooks.
Owin Startup system with optional support for DI/IOC.
Allows your owin app return content from ./well-known folder of your app in order to obtain SSL certificate from Let's Encrypt service
Owin Middleware module for site mail.ru. Working fine with mvc 5.
Owin Middleware module for site yandex.ru. Working fine with mvc 5.
Provides OWIN Middleware to access LiquidProjection over HTTP.
Monitoring middleware implementation based on OWIN interface defined in Microsoft.Owin NuGet.
Zipkin instrumentation for Owin based on the Zipkin.net library (https://www.nuget.org/packages/Zipkin/). It allows to automatically log every incoming HTTP request into Zipkin.
OWIN middleware for Raygun.io
Add to Owin and get restful and signalr interfaces for CRUD operations with any Json data.
Infrastructure for an IoC container adapter into OWIN pipeline
Middleware that enables your application to make use of GitHub's authentication.
PRE-RELEASE, do not use (but now supports SignalR).
ASP.NET Web API adapter for OWIN IoC container adapter