I bet you've never seen this before... I wrote a C# program that communicates with Flash over LocalConnection.
I can't give you a live demonstration because I don't want any to decompile the C# executable, but here's a link to a captivate demo showing it in action: Using LocalConnection to send data between C# and Flash.
In the demo I'm only sending string values, but you can send just about anything over LocalConnection. On the Flash end, just use LocalConnection like you normally would. On the C# end, I've created a LocalConnection class that behaves in a similar manner. In Flash I can call a C# method directly in this manner.. it's very handy actually.
Currently I have no plans to release this code (I'd like to get MM's blessing first before just putting it out there). If you know anything about operating systems and know how IPC works you can probably figure it out on your own though.
This opens up a whole new world of combining Flash and .NET. Next steps are to flesh out a decent API (mine is a little rough around the edges since the above demo was just a proof of concept), and then port the code to Linux and OS X as well. LocalConnection behaves differently on each operating system because, well, each OS does IPC in a different manner. The quest for the cross-platform Flash projector continues...