If you don't have an iPhone 4S, but still want to experience Siri, chances are you've already done so through one of a variety of existing methods.
Since the iPhone 4S was released, numerous methods for providing Siri, or at least some form of her, have appeared for older devices.
AssistantServer Installer is yet the latest way to do so, and the cool thing about it is that it requires minimal configuration to get it up and running at a very basic level...