When I interviewed Geoff Huston, chief scientist at APNIC for a podcast earlier this week. He mentioned that as IPv4 addresses run out we could end up with a free market where enterprise users are charged for new IP addresses. At the moment businesses pay a nominal admin fee to obtain a block of 255 addressses.. But as numbers dwindle, market forces, supply and demand could lead to users paying large feess for IP addresses.
Worse still, a black market could emerge if ISP are unable to obtain IP addresses for enterprise users. Huston believes buying and selling of IP addresses in an uncontrolled manner could irreparably damage the internet.