Sex, lies and CCTV

Up to a point, being paranoid makes sense. After all, people really are talking about you behind your back, colleagues are working tirelessly to undermine you and death really does stalk in your shadow.

Meanwhile CCTV cameras track your every move, while your employer taps your phone and monitors your e-mails. Under these circumstances, not being paranoid requires a wilful misinterpretation of the facts.

Most of us know, however, that paranoia is not something one wants to indulge too freely: it feeds on itself, destroys reason and consumes all your free time. Eventually, paranoia can become a bigger problem than any real-life worries. It needs to be kept under control. It's all a question of balance.

Recently, this balance has been disturbed by the sound of tills ringing. Companies are keen to cash in on your paranoia with the aim of offering you 'peace of mind', like there's such a thing. New products aim to help you prove that everyone is lying to you; that your spouse is cheating, your nanny is stealing and strangers are drugging your drinks ? or not, as the case may be. Whatever your suspicions, you are encouraged to give in to them. Forget about trust: trust was fine when we didn't have anything better, but now we have the technology to know for certain. Here are a few of the latest paranoia products for sale:

The surveillance system

Security issues are one of the biggest sources of paranoia, part of the price one pays for having anything worth stealing. The ability to monitor your home's perimeter normally comes at a high cost, but Spymaster of Mayfair now offers a home CCTV system for budget paranoiacs: the Eyecon. Does this sound like a good idea to you? If you had the telly in your bedroom connected to a security camera, would you ever sleep?

I was able to borrow a basic Eyecon package from Spymaster, but I didn't dare hook up the camera outside ? I was afraid someone might nick it. I did, however, temporarily install it as a 'kindercam' so that I could keep an eye on my seven-year-old son without looking away from the TV, which has always been sort of a dream of mine.

It was simple enough to install the discreet camera in my son's bedroom - if you don't count the part where I fell off the flat roof when the drainpipe came away in my hands. In no time, I had him coming in on channel six, sound and all. He spent most of the evening waggling his bare behind in front of the lens, which was only marginally more entertaining than Homefront.

Eventually, he fell asleep, and it became a bit like a Warhol film: stupefying, yet somehow compelling. I found myself flipping back to it again and again. I briefly imagined hooking up the maximum six cameras to the set-top box, so that I could monitor all the rooms, plus both the front and back doors, and the alley running alongside the garden. Then I'd never have to watch regular telly again.

The Eyecon standard camera system costs £250 plusVAT. Stockists: 020 7486 3885; www.spymaster.co.uk

The lie detector

Why shouldn't you own your own lie detector? The Professional Truth Machine - 'your key to detecting who is telling the truth? and who is not' - analyses frequency changes in the voices of people who you think may be lying to you. It's a great way to liven up a quiet dinner for two, and its maker says it's even capable of determining the honesty of people on the telly.

The flashing red, yellow and green lights are a bit difficult to interpret, especially if you're trying to carry on a conversation, but they look pretty. I hooked mine up to my phone for an instant assessment of the honesty of anyone who rang me, but in the end it only served to point out how often I lied to callers. This I know already.

The Professional Truth Machine costs £33.95, plus £2.95 delivery. Stockists: 0870 745 4797; www.paramountzone.com

The cheat test

Just how much peace of mind do you think you'll get by testing your spouse's pants for traces of semen in order to prove he or she is having an affair? That's what CheckMate, the new five-minute infidelity test kit, enables you to do.

It works on men and women - or rather on their pants - and you can get six tests out of one kit. There are only two outcomes here: no news and bad news, and in the meantime you've been fishing through the dirty linen with an eye dropper.

Obviously, people will do all sorts of unattractive things while in the grip of paranoia, but if you've got to the stage where you're doing forensic work on your spouse's undergarments, you might as well accept that your relationship is in trouble no matter what the test results show.

CheckMate costs £59.99 per kit (there's currently a two-for-one offer, if you're feeling ultra-paranoid). Stockists: 01582 696 911

The health test

SureScreen Diagnostics offers home-health kits including tests for bowel cancer, syphilis, liver function or impending heart attack. Again, if one is to get peace of mind, one must first overcome a resistance to messing about with bodily fluids. I decided to test my cholesterol, on the basis that it only required some of my blood. It certainly seemed preferable to posting a stool sample to a complete stranger.

Somehow, I lost the instructions, but it seemed self-explanatory: there was a gauge showing cholesterol levels, and a well with a picture of a finger dripping blood into it. I fetched a pin, ran it under flame, jabbed myself and squeezed a few drops into the chamber. Nothing happened, so I let it sit for a while. Five minutes later, the white line by the gauge had gone grey up to the halfway point. The chart said I was in the 'normal to high' range. For the first time in my life, I began to worry about my cholesterol. I double checked, but by now the grey column was three-quarters of the way to dead, and rising. Eventually, it rose to the top and a dot marked 'End' turned bright green. It seemed I had but a few minutes to live. I tried to calm my racing heart, fearing for my furred-up, claggy arteries. I tracked down the instructions on the net, and discovered my mistake. I had put nowhere near enough blood in the thing. I tried to jab a few more fingers, but this is the sort of task that gets harder with practice, and I soon gave up. As far as my actual cholesterol levels go, at least now I know I'd rather not know.

The At Home Cholesterol Test costs £4.50. Stockists: 0500 864 460; www.surescreen.co.uk

The drug test

Many kits enable you to test your children or employees for drug use. The latest ones require just a strand of hair from the addict in question. For personal use, there are Proofies - dip strips designed to tell you if someone has spiked your drink with the date-rape drug Rohypnol. I used them for a week, and the consistently negative results went some way to restoring my faith in humanity. Of course, I have no way of knowing if they work. To prove it, I'd have to get some Rohypnol, not a thing I'd like to be seen to be shopping for.

Proofies (3) cost £4.99 plus VAT. Stockists: SureScreen, as before