Hitachi announced their latest, smallest RFID a few months ago, and I've just recently become aware of it. You can click here to see it. I believe it would be worth your while to do so. By way of comparison, here is its bigger, older brother.

When I first heard of RFID technology, the devices were about the size of a credit card. You would attach them to whatever you wanted to track using strapping tape. That was less than ten years ago. Today we're looking at a silicon fleck, .15 millimeters on a side. Progress.

So how significant are these motes? Well, to be honest, in the Big Brother Is Watching You department, not very. They are nowhere near to having the capabilities of the mythical Qeng Ho localizer, or even its humbler real world inspiration. It has no sonics, no light sensors, no ad hoc mesh networking. No direct optic nerve stimulation via phased array transmission, for that matter. In fact, all they can do is identify themselves. They give a tiny little squeak-back when you tickle them with radio waves. Nevertheless, I do worry. It's Moore's Law, you see. If these things continue to improve as they have, in twenty to forty years their capabilities should be increased anywhere from a thousand to a millionfold. That's when things will get really interesting, though I suppose it needn't be all bad. Perhaps not even mostly bad. Still, a little worry now might save us considerable grief later. Just so you know.

For some reason, that image of tiny RFID chips with salt crystals has me thinking about Bob Shaw, a science fiction writer whose work I've not read in thirty years or so. He was one of those rare SF authors who truly advanced the conceptual state of the art. These days most people are at least passingly familiar with the standard science fictional props. They know what a hyperdrive is supposed to do, you step on the gas and you go. Likewise, a blaster is trivially easy to understand as a space six-shooter. It's actually a bit of a shame, what Lucas and company have done to the popular conception. Star Wars hand weapons are positively anemic compared to the rather more emphatic blasters of my youth. Those Buck Rogers antiques combined the best features of an atomic flame thrower and a recoil free hand-cannon. Imagine a light saber with a two hundred yard reach and you're almost there. Captain Flandry would have sneered at Han Solo's pokey little popgun.

But, all fun aside, science fiction can be far more than just rocketships and rayguns. It can tackle stranger, more original concepts, and Bob Shaw is responsible for one of my favorites.

Going far beyond the standard beloved cliches of the genre, he used a classic application of the "What if?" technique and posited a substance that could impede the progress of light by a factor of quadrillions. He called it slow glass.

A ray of light entering a pane of slow glass might take years to reach the far side. You, after waving and mugging at a pane of such stuff, might come back in five years, or ten, and circling round to the other side of the glass watch your younger self happily clowning as the tardy photons bearing your image finish their slow trudge across the millimeters and burst out into freedom.

What if we could synthesize such a material? What would we do with it? The easy answers came first. Rustic views for the everyman, indistinguishable from reality. An end to electric street lighting.
Other, more complicated scenarios can be imagined, and one such is freely available online, the award winning short story Light of Other Days. If you've never read it, here is your chance. I hope you'll take the time, as it's quite good.

Gregory Benford once remarked that writing science fiction without limitations is like playing tennis with the net down. Without difficulties, there can be no drama. For most of his slow glass stories, Shaw followed this dictum, adhering to a self imposed set of limits. Once fabricated, slow glass couldn't be manipulated. You couldn't fast forward. You couldn't rewind. Tampering with the glass caused it to release all of its stored energy at once. Bad idea. If you wanted to view a particular event, you just had to wait it out.

I recall a story involving a court case where this "fact" was used to quite good effect. My memory of the story is a bit hazy, but it went something like this. The suspect had been tried, convicted, and executed. The evidence was fairly conventional (no video), but was believed to be as airtight as such things can be. Then, and here my memory grows extremely unreliable, it was discovered that a piece of slow glass had been present at the scene of the crime. Perhaps the court had the glass all along, but felt that sentencing couldn't wait? No matter. Years after the fact, far too late to do any good, the judge and jury would be able to know if they had killed an innocent man. Oddly enough, I can't recall which way it went. What I do remember is the sickening suspense as the glass counted down to the fatal minutes.

That story and many others are available in Shaw's collection, Other Days, Other Eyes, and the final story in that collection is where the connection with Hitachi RFID chips comes in. Were you wondering if it ever would?

In that story, in short, scientists finally achieved the Holy Grail of slow glass research and learned how to access the glass's "memories" without triggering a huge explosion. Progress.

And what did they choose to do with their new triumph, their readable slow glass? Why, nothing but good.

First of all, they ground up tons of the stuff into fine crystals, rather like beach sand or sea salt. Then, they dusted everything with it, wholesale. Cityscape, country lane, lonely moor, whatever. So that forever after, no matter where you went, tiny bits of observant grit would tirelessly memorize your every move for posterity. And you could never be alone again.

It needn't be all bad. Nevertheless, I do worry.