Inside every Hewlett Packard laptop, and perhaps others as well, I'm told, is a tiny device -- a sensor -- known as an accelerometer. It's just what it sounds like, a way to measure acceleration. Should you accidentally drop your laptop, the sensor's job is to protect the hard drive from damage by sending a signal to park the read/write head away from the drive. Amazing, no? (Please do not test this out at home.)

I learned this today from Jeff Wacker, an HP Fellow, a researcher and a futurist, who came to Washington to talk to policy-makers and reporters about HP's work on sensors, and how they will change the way we interact with the world. Sensors will, he argued, help conserve energy, improve traffic congestion, track food-borne illnesses, even save lives. HP is working on a project called CeNSE -- the letters stand for Central Nervous System for the Earth -- which is about communicating with all the stuff around us, as well as with the planet itself.

CeNSE, the company says, will "revolutionize human interaction with the earth as profoundly as the Internet has revolutionized personal and business interactions." The idea behind CeNSE is also known as "the Internet of things." (See The Internet of parking spaces.) IBM with its Smarter Planet efforts and Cisco, which has its own futurist who's thinking about this interconnected world, both see the opportunity to develop the Internet of things as potentially huge.

It sounds futuristic -- and one would expect nothing less from Wacker, whose bio [PDF, download] says that he is a "long time professional member of the World Futurist Society" -- but, as it happens, sensors in general, and accelerometers in particular, are already part of our daily lives. HP's printers rely on a tiny accelerometer (actually, a microelectromechanical system, or MEMS) to neatly deposit ink on paper. "In every print head, there are MEMS," Wacker told me. "They are looking at how many dots are being spit out by that inkjet head to see how much ink is going on the paper." Accelerometers tell airbags when to deploy in cars. They're inside consumer electronics like Nintendo's Wii motion controller and Apple's iPhone, which is how the phone "knows" when it is being shaken or turned.

Wacker and his colleagues at HP Labs are working on sensors that are 1,000 times more sensitive than the ones in broad use today. Earlier this year, HP announced the first major deployment of these super-sensitive devices, a collaboration with Shell that will use wireless land-based sensors to pinpoint new oil and gas reserves beneath the earth. It's unfortunate (if you care about the environment) that the first use of these sensors is to discover fossil fuels, but they are intended to help Shell find oil and gas more efficiently, which may or may not be a good thing.

It's easy to imagine many more uses for these sensors. Wacker talked how the smart grid will depend on sensors, so that utility companies can cycle down home appliances when they are not in use to save energy and save their customers money. He talked about a mother coming home from the grocery store, and using a sensor to identify enzymes in produce that could signal the presence of e coli bacteria. He talked about aging baby boomers using sensors in their cell phone that would be able to monitor their cardio-vascular health, and deliver warnings during exercise when it's time to take a break. "We boomers can wear a sensor network that can monitor our arteries and our exertion and say, 'don't do that or you're going to wind up dead,'" Wacker said.

I asked Wacker what obstacles stand in the way of making HP's CeNSE vision real. It turns out that there are many. "The cost of making a sensor has been too high," he said, but they are, of course, coming down. Sensors need to be powered, either with tiny batteries or "parasitic power" which would enable them to draw energy from the sun or heat or vibration. Spectrum needs to be available so that sensors can talk to one another, and to consumer devices. Information has to be analyzed, integrated and delivered to people in a way that's useful, most likely over their mobile devices.

Pulling out his own cell phone, Wacker says: "This thing will be my radio to tune into the music of the world."

Here's a two-minute video in which Pete Hartwell of HP Labs talks about CeNSE.