title: C#/WPF FileSystemWatcher on every extension on every path
body: <p>I need FileSystemWatcher, that can observing same specific paths, and specific extensions.
  But the paths could by dozens, hundreds or maybe thousand (hope not :P), the same with extensions. The paths and ext are added by user.</p>
  
  <p>Creating hundreds of FileSystemWatcher it's not good idea, isn't it?</p>
  
  <p>So - how to do it?
  Is it possible to watch/observing every device (HDDs, SD flash, pendrives, etc.)?
  Will it be efficient? I don't think so... . Every changing Windows log file, scanning file by antyvirus program - it could realy slow down my program with SystemWatcher :(</p>