The first time I used my iPhone 3GS as a navigation device in my car a few problems were quickly an issue. First, there is nowhere to place the iPhone in my car where it is easy to see. Another problem was that the battery doesn't last long and then the volume from the speaker is too low to hear spoken directions well.
NewerTech can't help with the volume or battery life, but the company has announced a new window mount for the iPhone 3G and 3GS that will keep the handset in place while you drive. The product is simply called the Window Mount for iPhone 3G/3GS and has a suction cup on one end and an articulating arm on the other.
The overall length of the mount is 9-inches and it works with both the iPhone 3G and 3GS as the name implies. The holder end of the mount rotates and allows the phone to be held in portrait or landscape modes. The mount is available now for $19.99 and can hold your phone on your desk as well.