Did you know that iPhone screen is completely Scratch Proof? I guess you don’t want to take any chance. But believe me, iPhone screen is made out of a 100% scratch free material. I have been using iPhone 3G from quite sometime and don’t have any scratch what so ever on the screen. In fact I found this dicussion thread on Apple Forum which re-iterates the same point:

• You don’t need a screen protector, in fact a lot of the Apple Geniuses don’t use one. I use the Power Support crystal film, I like having it on. You don’t even see it when applied right. You never know when Murphy’s Law kicks in.
• Honestly you really don’t need a screen protector. But if you tend to have coins or keys in the same pocket, then you’d have to be careful, but if you are careful with your iphone, then you don’t need a screen protector.
• Have had my iphone for over 14 months. never used a screen protector and have no scratches on my screen. I will tell you that, although I keep it in my pocket all day long, I don’t keep it in a pocket with my keys. You might want to avoid coins too. Otherwise, i find the screen to be very durable, unlike my Palm screen. 

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