Fascinated by GeekMorgan, the dude who made his own custom iPhone 3G GameBoy case, I decided to review the Agent18 Slim ClearShield iPhone 3G case myself (Amazon $23 shipped). For those of you unfamiliar with Agent18, they are a small firm based out of SoCal making pretty cool accessories for iPhones, iPods and even Zune products.
The Slim ClearShield has a pretty basic two-piece sandwich design holding the iPhone 3G in the middle. Ever since an incident I've had with my Griffin ClearBoost coming apart after I dropped my old iPhone to the ground, I have been preferring the slider-style cases (ie. Griffin Clarifi, Incase Slider, etc...). Agent18 Slim ClearShield, however, has a pretty sturdy clip design holding the two halves together nicely; as a safety, I did affix very small strips of clear tape to support the corners for added holding strength. Overall, the case is very easy to use, it comes with a screen protector, iPhone 3G dock adaptor (so you can use OEM dock to charge w/ the case on, very smart!) and two other Agent18 swapable badges (light gray and green colored). The cutouts are large for easy access even if you have fat fingers. With the case installed, your iPhone will remain its classy appearance without adding too much bulk to its overall dimension.
I did some research and have concluded that this is probably the best case to make your own iPhone 3G Gameboy case. For some reason, its quite hard to find all clear cases for the iPhone 3G. I am arranging a review unit of the Griffin iClear for iPhone 3G to see if I can produce a custom case of my own coming up, stay tuned.
Overall, if you want a no-frill, high quality clear case for your iPhone 3G, Agnet18 makes a very solid choice. MSRP $35