Can I catch the Fn+F3( or Fn+F2....) keys with my program?
@Leo, the main function of the Fn is change the scancodes of other keys on the keyboard, unfortunately the Fn key usually (in some systems this key returns an ScanCode) doesn't have an scan code, additionally the behavior of this key is not standardized as other keys (Ctrl ALT) because of this is very hard detect or intercept when this key is pressed.
You can check theses links for more info