Many people have been waiting for the eve of the iPhone 3G's introduction to pounce on cheap first generation iPhones on eBay and Craigslist. These people are upset. For some reason, contrary to what you'd think, first generation iPhones are going for astronomical prices. Craigslist is full of people offering up to $600 for 16GB iPhones and up to $400 for 8GB models. The arrival of the app store might be part of it, and the fact that it'll be harder to get a 3G iPhone without contract, but $600 for a 16GB iPhone is crazy. Who wants to buy my iPod touch?
I have to say that for some reason I find the first iPhone so much more revolutionary, more solid because of its metal parts and MORE DISCONTINUED that I have no problem understanding the increase in price - I predicted it to be honest. It just somehow... ages better IMO :)