Solid Architecture for Quality ASP.NET AJAX
Shell extensions with .NET Framework are definitely possible. Maybe a bit boring. See a (working) example here from TheServerSide.NET.
My brother has some code for doing this on GotDotNet http://www.gotdotnet.com/Community/UserSamples/Details.aspx?SampleGuid=08ccce00-b2ba-4bee-9c29-a18f3ad85a65
Dino, the link to the article is broken (inserted it twice, eh?). It should point to http://www.theserverside.net/articles/showarticle.tss?id=ShellExtensions
Dino, is there some place where we can download the sample code that was mentioned in the article?