If you thought Siri was impressive, wait till you see what a couple of hackers have managed to do with the Apple service.

Rather than you having to talk to your phone, they’ve devised a way of just getting it to respond based on what you think.

Called the Black Mirror Project, it looks like it is something from a sci-fi movie, like Strange Days or Johnny Mnemonic, rather than really put together by some guys messing around.

The currently rather crude looking prototype involves an iPhone 4S connected to a setup that uses a MacBook Pro and an Arduino open-source microcontroller, along with electrocardiogram pads that are attached to the head of the "test subject".

The Arduino is set up with a program that recognises Siri commands from the ECG pads and sends them to a voice synthesiser, which then feeds the commands into the iPhone's microphone jack. You still need to press the home key on the iPhone 4S to turn on Siri, but the duo hope to automate this in the future.

The two have started a Kickstarter page looking for funding to make this an actual product.

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