Introducing Protocol Handler.NET
"Protocol Handler.Net is a set of .Net wrappers for the protocol handler interfaces that enable developers to create and deploy protocol handlers for SharePoint search and Search Server.
Developers can index data and documents from any system they can connect to.
Much of the complexity and time around the development of protocol handlers, such as COM interoperability, are reduced and hidden in the wrappers themselves letting developers just concentrate on code to connect to a content source and pull data.
Protocol Handler.Net makes it possible to develop protocol handlers in C# or VB.Net and simplifies the handling of security, metadata, streaming content, deployment and management just to name a few things. It also comes with a help system and sample project to further help developers."
Big thank you to to Chris Gomez from http://www.FastSharePoint.com for creating and sharing these tools and samples!