In case any of you are interested in OWIN, here's the spec...it's a very short read. Katana is Microsoft's implementation of OWIN (that's the thing that starts with "K" that James metioned.")
It's essentially a way of inserting application delegates in a web request / response pipeline. You'll see heavy use of it in vNext. You'll see glimpses of it in asp.net mvc5 for authentication and SignalR. Your application delegate is given a dictionary that has the headers, a request stream, a response stream, and other things. The spec establishes some rules for lifetime and completion of your application delegates.
Here are some things that I think OWIN might be good for:
- Authentication (obviously)
- Transport protocols (obviously)
- Compression
- Encryption
- Logging and statistics
- Looking for exploits (people using the exploits...)
- Diagnostics
- Protocols like RSS where you might want a global way to authenticate and intercept a post.
- Out of band traffic that might be used by a client...this case might be interesting to explore.