If you are looking for a skin, cover or case for iPhone 3G, invisibleSHIELD
from ZAGG is the best. It is an indestructible film that will protect iPhone 3G from scratches. This technology (nano-memory) was also used for high-speed helicopter blades against dirt and debris in military industry.It is currently the toughest, most durable and thinnest (yes, it is only .2 millimeters thick) protection you will find. Lifetime guarantee is provided to back the product. If it gets a scratch they will replace the film for free. If you later need to remove it, it is not a problem as well, It leaves no sticky residue.
