There’s a new iPhone 3G coming out in July. If that statement shocks you, you might want to check your connection. We love new shiny hardware, but what we’re really interested in is the number of “old” iPhones that are going to be hitting the market. Many people will be ditching their 1st generation iPhones just to get GPS and 3G. This abundance plus the new $200 price tag is bound to depress the price for used phones.

A used 1st generation iPhone is actually a pretty attractive device. It’s already been laid wide open by hackers so you can run pretty much anything you want on it instead of waiting for the App Store to tell you what you can and can’t do. You could use it as a WiFi Voip phone, a simple web pad, run an NES emulator, use it as a musical instrument, or build an army of robots.

What will you do when the price of used iPhones bottoms out?