JR Hill has released screen protectors to keep oils and scratches from ruining your G4 PowerBook LCD screen. The leather grain pad slides between the PowerBook screen and the keyboard and is available in several colors. According to JR Hill:
We have a new product to announce today. Its our Full Size PowerBook G4 Screen Protector. It seems from many emails we have received from customers that the track pad button is also touching the LCD screen of the super thin PowerBook G4 as well as the keyboard. Our new Full Size Screen Protectors now cover the whole area of the keyboard / trackpad button giving FULL protection from dirt and oils and scratches getting onto the LCD screen. The Screen Protector measures 12 3/4" x 8 3/8" and, like our original Screen Protector, is available in Black, Burgundy, Green and Blue.
You can find more information about the Screen Protector at the JR Hill Web site. The full size PowerBook G4 Screen Protector is available for US$17.49.