The Leica icons set for Mac OS created by Andrew Sigurow is a great collection that includes 180 high quality icons featuring photographic cameras manufactured by Leica Camera AG from 2000 till 2012. The available .PSD, .ICNS and FOLDERS versions will give you an original touch to your desktop no matter the file types or applications you choose to associate with the icons. Here are the download links:
Screenshot of some of the available icons: