title: Creating Virtual Folders and hooking them into the file system
body: <p>I have a big collection of folders for projects I'm working on. I've been trying to find a better way to sort them all for a long time and I want to write an app that creates groups based on whatever criteria I say, such as "folders from 2011" or "folders containing a x type of file" etc. </p>
  
  <p>This is fairly straightforward, and wouldn't present much of a problem to code using its own UI in winForms or WPF or something. But I think it would be far better if I could make these folders appear to be part of the filesystem, so other apps (like existing file explorers) can see them.</p>
  
  <p>Is this possible? Would it cause problems I haven't considered? How do I go about doing it if it is possible? </p>
  
  <p>One way I thought of doing it would be to have the app monitor the filesystem and create folder shortcuts every time there's a change, but I'm curious about whether its possible to actually present a fake filesystem to explorer through a 'gateway' folder</p>
  
  <p><strong>EDIT:</strong> Ok it's obviously possible since <a href="http://www.virtualfolder.net/">http://www.virtualfolder.net/</a> can do it, and now that I think of it so can <strong>TrueCrypt</strong>, although it would be nice if it didn't have to appear as a separate drive. So the question becomes, how do I implement it? </p>