Wii: More than just a game

Remember the buzz when Nintendo unleashed its Wii console the Christmas before last? If you'd pressed your nose up against the window of any computer games shop in Britain, you probably would have witnessed enthusiastic punters waving around a white device slightly larger than a mobile phone. If you had investigated further, you would have seen that they were playing a game of virtual tennis, or maybe golf or bowling. It seemed the height of interactive computer gaming.

Well, it turns out that sports games were merely the foothills of the Wii's capabilities. Now a whole range of possibilities has come into view – and the startling thing is that Nintendo has not hit upon its most amazing uses. Instead, these have been developed by legions of devoted gamers – or Wii-jackers, to give them their full name.

The white box used to control the Wii is a hi-tech marvel, a wireless gizmo packed with motion detectors and infrared sensors. It is intended by Nintendo to play the role of tennis racket or golf club as people swing it around their living rooms to hit the perfect shot. But the Wii-jackers had other ideas. What if, they thought, the handset could be used with other gadgets? What if it could be used to control a computer or a vacuum cleaner, or even to create an interactive music-mixing gadget for those musicians who like to dance while they work?

Some 25 million Wii consoles have been sold worldwide, putting a lot of these gadgets into the hands of some seriously creative people. Their success starts with an understanding of what makes the Wii so revolutionary. Rather than just having buttons and joysticks, the Wii handset, or "Wiimote", is motion-sensitive. It features an accelerometer, a device that accurately records how fast it is travelling, in three dimensions: backwards and forwards, up and down, left and right and rotating in any direction. It also has an infrared camera, which works out where the handset is in space, relative to the screen on which the games are being played. Finally, there is a wireless communication that feeds all this data to the console.

The marvellous upshot is that the console can detect the handset's position in 3D space and track its relative motion on a screen. This is what enables users to hit non-existent tennis balls, operate a virtual fishing rod, and all the other functions of the Wii, without being physically connected to the console.

The Wii-jacking breakthrough came when computer programmers and gamers managed to channel the Wiimote's instructions not to the Wii console but to their own computers. Consoles can only run games that have been developed and approved by the manufacturers. But computers can do a whole lot more. And, crucially, they can run programmes written by independent developers. In the past year, techno-whizzes have exploited this facility to use the handset to perform all manner of tricks.

Several developers have managed to use the Wiimotes to control their Roomba robot vacuum cleaners. Others have rigged up a system using some independently developed software called DarwiinRemote, so that the controller can be used to scroll through programmes on Apple computers with a flick of the wrist.

Johnny Chung Lee, a computer engineer at Carnegie Mellon University in Pittsburgh, and hero to the Wii-jacking community, has developed a "head-tracking" programme. The software enables users to create a 3D virtual reality display on their monitors. The user wears a pair of glasses fitted with two small infrared lights, and the image on the screen shifts with each movement of the player's head. Lee has also designed software that allows people to use their Wiimotes to create interactive whiteboards, as well as a system that allows them to manipulate on-screen files simply by using their fingers and a bit of reflective tape. Think Tom Cruise moving computer files with his hands in Minority Report.

The computer game company EA has just unveiled a new Wii game designed by Steven Spielberg. Due to be released in May, it incorporates a technique that looks very much like Lee's head-tracking programme.

But perhaps the most commercially savvy use of Wii-jacking so far has come from a former post-graduate student at Edinburgh University. Yann Seznec, a Franco-American sound designer, has used the handset to create a musical instrument like no other. Dubbed the "Loop Machine", it enables users to load audio files such as a drum pattern or a baseline on to their computers. These "loops" then automatically sync with each other. But the really clever part of Seznec's invention is that these samples can be manipulated by moving the Wiimote around. The end result is that the user can dance about with the Wiimote in their hand, making music and performing at the same time. You can even record a set of movements and apply that same set of movements to particular sounds.

A new improved version of his Loop Machine has just been completed and is now being sold online for US$20. Download it on to your computer, grab your Wiimote and you're away.

So how is it all done? Surprisingly, no screwdrivers were used by any of these Wii-jackers. All that was needed was a Wii controller and a computer that's capable of using a Bluetooth mouse and keyboard.

Seznec explains that the key is persuading the Wiimote to link up to the computer, rather than the games console. Seznec did this by downloading some open source software written by a Japanese software developer named Masayuki Akamatsu (yet another hero of the Wii-jacking revolution).

Seznec says that hacking into the Wii remote – that is, pairing it to a computer – is relatively easy. What's hard is doing anything useful with it. For the Loop Machine, this meant Seznec writing his own computer programme. "It's important to make systems that use movement in a logical way," he says, "so that when a certain movement is made – be it an upwards swipe or a circle – a certain sound or effect is created. It's hard to do that, but I came up with various programming tricks in the end. I've put maybe a thousand hours of work into this project."

So what are the ethics of all this? Will Nintendo crush the Wii-jacking revolution as it starts to make money? The independent developers often describe themselves as "hackers" and "homebrewers" (because they prefer to make their own programmes). But despite the stigma that surrounds interfering with technology for many lay people, there is no suggestion that what the Wiijackers are doing is illegal.

My attempts to get Nintendo to comment on Wii-jacking crashed into a wall of silence. But Seznec guesses that there might be an element of calculation from the manufacturer involved in the whole phenomenon. "Nintendo has made it really easy for independent software hackers to use their hardware, and some people suspect that they did that on purpose to encourage development."

He points out that the company didn't have to use Bluetooth in the console. Bluetooth is an industry standard, used by all kinds of wireless gadgets, from mobiles to hi-fi speakers. It's meant to be versatile, so that a phone can link to a headset, a computer and even a photo printer, all at the same time. Microsoft's own wireless controller uses a different system altogether, one that's much more difficult for the hackers to work with. And even if Nintendo did want to use Bluetooth, the company could easily have encrypted it. "They're not idiots," Seznec says. "My suspicion is that people in Nintendo are sitting back and letting people get on with it."

Lee is more cautious but does say: "My perception is that they are relatively neutral [about it]."

Whatever the truth, things are changing in the world of computing and gaming. There appears to be an urge to be "creative" with technology, something that has become possible thanks to the rampant idea-swapping on internet sites and through how-to videos on YouTube. Lee's demonstration of head-tracking on the video-sharing site has registered more than four million hits.

The question now is whether Nintendo and other big firms will start to work with independent software developers, tapping into their expertise to manufacture new products and applications. Opening up the secrets of their hardware would be a good start. "There's a very concrete argument to be made that Nintendo should be more open and that [the inventions created by hackers] would add value to their product," says Lee.

The possibilities are certainly causing excitement among computer nuts. "It's absolutely fascinating," says Seznec. "If Nintendo can start pushing the independent thing, it offers the possibility of a totally new environment for gaming."

Watch Johnny Chung Lee's head-tracking application

What your Wii can do for you

Control your Mac

Download DarwiinRemote, a piece of software, and you can replace the Apple with your Wii controller. Some have posted their achievements on YouTube. To download the free software visit http://sourceforge.net/projects/darwiin-remote.

Get the vacuuming done

Are you one of the 2.5 million owners of a Roomba robot vacuum cleaner? Then sit back and take charge of the housework from your most comfortable chair. To download the necessary software visit http://spazout.com/roomba.

Turn your computer into a whiteboard

Electronic whiteboards cost hundreds or even thousands of pounds. This free software lets you turn any computer display or projector into a whiteboard. Download the software from http://www.cs.cmu.edu/~johnny/projects/wii.

Be a music maker

Yann Seznec has invented a new musical instrument. He's asking $20 (£10) for the software. It lets you load up samples of music and mix them together as you dance by waving the Wii remote in various patterns. Download it from http://www.theamazingrolo.net/wii.