iPayPhone simulates the buttons of a pay phone, playing the sounds of each button you press. This application does not actually place calls from your iPhone. It is only for amusement.

Sidenote: At the point of posting this program has been marked as beeing freely available without costs. As this program is hosted with the AppStore the status might change. Authors like to publish their programs for free for promotion purpose and then make it commercial. Also it could happen that the author decides to take the program down.

http://appshopper.com/entertainment/ipayphone