Begun your holiday shopping yet? If not, I've got just the thing for the fusspot who insists on something new and different. It's the spitting image of a pocket calculator (which it's not). It has all the symbols one might expect -- plus, minus, multiply, divide. There's even a light-emitting diode display. It would fool just about anybody . . . and that's precisely its purpose. No one possibly could imagine that this very-ordinary-looking phony calculator was masking a revolutionary new product -- a miniature lie detector, would you believe. And the price: only $149.95.

The implications are downright scary. If the product truly works, it could signal the end of trust in America (as well as everywhere else on this globe).

But before telling you more about this unique item, as well as a similar product that looks like a small portable radio, let me back up a bit. Last April -- in a column that probably elicited as great a response as I've ever had -- I wrote about a $29.95 digital watch what was supposed to be on the retail counters before Christmas. But wow, what a watch. Not only was it designed to tell time, but it could enable the wearer to detect without the subjects's knowledge whether someone was lying or telling the truth by measuring the amont of stress displayed in that person's voice. So at least, was the claim of its creator, CCS Communication Control , a New York-based, fast-growing manufacturer of sophisticated security devices.

However, there's a new wrinkle. CCS has replaced the $29.95 watch with that $149.95 calculator I mentioned earlier. And therein lies an interesting tale.

CCS Vice President Carmine Pellosie, a former bank security boss, told me the change had come about because of strong negative reaction from certain government agencies whom he refused to identify. "We got thousands of requests for the watch (from teen-agers and housewives as well as excutives and I think we could have sold a million of them," he said. "But we also got a loud and clear message from the government: It didn't want 40 million people walking around judging everbody else's integrity on the ticks of a watch.

"If the watch could have been though of as an adult toy -- capable to some degree of bugging somebody else's mind, but not a professional machine -- we wouldn't have had any problem. But too many people thought of it as an infalible lie-detecting instrument that required absolutely no training . . . and that was wrong. So we tabled the watch.

Pellosie noted importantly that economics had also entered into the picture -- what with Uncle Sam accounting for about a third of CCS's annual volume.

But what happens if the government also objects to the new model? I asked.

Pellosie doubts that will happen. The higher-priced version relfects a greater quality of engineering, far more expensive components than would have been placed in the watch, and includes a free training course, he said.

Maybe so, but not to the critics. Some heatedly argue that the voice stress analyzer -- first used at the end of World War II as a means of establishing voice indentification as military installations -- is immoral and a clear invasion of privacy. And some insist -- with studies to back them up -- that the validity of the VSI's findings is highly questionable.

Pellosie's reaction: "The validity of the VSI has been proved time and time again. If our new machine (the calculator) does what it's supposed to do- which it will -- you're really not invading someone's privacy, but getting at the truth. And what's wrong with that? I've always thought it was immoral to lie."

Here's the way the four-ounce phony calculator will work. In response to question -- the best results are obtained within 10 feet of the unit --a bar display will instantly light up in color. A green bar indicates no stress; yellow, mild stress; and red, stress (implying deception).

Another model, the one that looks like a radio, goes for $199.95. Weighting 9 ounces, it has a large numeric display across the front, automatic and manual controls and the capability of being plugged into a tape recorder (enabling you to analyze the results later on). A no-stress reading is reflected in a numeric response of 20 or under; mild stress 21 to 35; and heavy stress, 36 to 60.

The first run -- 1,500 of the two products combined -- should be completed by early December. Thereafter, CCS plains to produce about 6,000 a month. "I don't think there's any question but that we'll sell every one we can make," said a confident Pellosie.

An accompanying booklet will cover sample interrogation practices and the kinds of questions to ask in formulating the most effective interview.

So there we have it -- another supersnooper gadget right out of James Bond. I'll leave a discusion of its merits to the experts. But I'd like to repeat what I said previously when I wrote about the lie-detector watch. What makes it so frightening and morally questionable is that in these times of political, business and even family distrust, a lot of people might well give credibility to a product that does little more than indict somebody on the anxieties on one's voice. It's a horrible thought.