So what do we have here? A very clear explanation of what is OWIN by Robert Muehsig (MVP). It’s a must read to finally know what OWIN is all about. Then there’s some way to optimize your MVC with Azure caching and compiled views and finally, we have an amazing multi-part tutorial on WebAPI. Don’t forget to scroll at the bottom of the article to see the other parts.
As for the tooling, we have Superscribe which is a routing framework that is OWIN-compatible and a small JavaScript tool that allow you to do client-side cropping (with CSS) with the correct data to do a proper server-side cropping. Perfect for cropping user profile pictures.
Happy reading 
OWIN
OWIN – what is it about and why is it so cool? | Code-Inside Blog International (ow.ly)
Azure/MVC
Instant Azure Caching with MVC (ift.tt)
Get Compile-Time View Errors in ASP.NET MVC (bit.ly)