As one of several different types of Capdase screen protectors for the iPhone 3G, Mira ($13) is a single sheet of translucent mirrored film that covers the device's entire glass face except for its ear speaker and home button. When the iPhone's screen is off, the surface looks as reflective as a mirror, but when it's on, you can see most of the screen's detail shining through. A cleaning cloth is included for initial application to the iPhone 3G's…