Since I bought the iPhone two weeks ago, people don't stop asking me questions about it. To make it short, they all go "wow, unbelievable !" first, then they ask me the question about the pricing : "how much is it ?". I then demonstrate the key features, i.e. the phone, the iPod, the web browser, the email, the camera, playing with the MultiTouch UI. Most of the time, this short demo is enough to convince the guy that 399€ is a fair price for such a jewel.
However, sometimes the guy goes "well, you may need it for business to spend so much money". I totally agree. The iPhone is THE perfect tool for new innovative businesses. Twice over the last week, I've been showing the iPhone to prospects - read : target customers for the consulting & training business I'm setting up. I simply explained which kind of new support and assistance services the iPhone could enable (for instance, how YouTube can be used for online training). Each time, I got the same reaction : "give it to our people, and you'll get the business with us".
Beyond that kind of new services based on existing/simple/standard features of the iPhone, you can create new ways of dealing with a problem, means you can create new/innovative solutions for your customers based on the iPhone. Watch this, and you'll get the picture.