IT'S never been easier to cheat on your partner. We have the technology - so we can lie our little heads off.

Since the mobile phone gripped the world firmly by the throat, there's been no hiding place every second of every day. People rely so much on these accursed contraptions, they have become joined at the hip. They take them to bed, lay them on the bath side, even drop them into the toilet from a shirt pocket as they stoop to flush.

But, until now, that instant availability has also been a curse for people seeking privacy.

In the old days, blokes stopping off at the pub for a sneaky pint could simply shake their heads when the landlord put his hand over the phone and shouted: "Are you in?"

Some licensees even collected cash for charity by charging a sliding scale of excuses like: Yes, he was here earlier; no, haven't seen him tonight; haven't seen him for weeks; never heard of him.

Spotting the liar is a game that provides huge amusement in pubs these days. He - or she - is the one who suddenly dashes outside to answer the mobile phone.

If it's daytime, it's probably the boss on the line, so a background noise of traffic sets up the "I'm just heading back from my meeting" alibi.

If it's evening, it is most likely an anxious spouse complaining that dinner's been ready for hours. The sound of a pub's jukebox, or clanking glasses, or the laughter of the opposite sex, just would not sit well with the fairy tale excuses that are about to be trotted out.

So if people will go to those lengths to deny having a drink, imagine what they would do if they were really cheating.

Commercial forces will always cater for our most base instincts, so enter the software company which is marketing fake background noises for mobile phones.

At the touch of a button, cheats can make sure the boss - or spouse - hears traffic noises even if they are still in bed. If the wife or husband phones at a delicate moment, just switch to office background (complete with the sound of clattering keyboards and other phones ringing) and claim you are still at work.

For just £7, the software can be downloaded from a website and the variety of background environments is endless. No doubt they will be offering a background of hymns and prayers for those wanting an illicit Sunday morning rendezvous. Oh, what a tangled web we weave.

But don't get too confident. Technology is available to both sides in this unholy war.

Miniature bugs and cameras can be bought over the counter, and you can bet your life there will soon be some firm offering to triangulate a person's whereabouts from his mobile phone signal, right down to the spot where his steamed-up car is parked in a country lane.

And perhaps a high street laboratory will offer DNA analysis to replace the old-style lipstick-on-the-collar detective work.

Don't bother with a private detective because as one sleuth once told me when I interviewed him, if anyone even decided they needed his services, their relationship was already over.

There are ways for the victim to fight back in all this. You could wait until he is separated from his phone - he'll either be snoring off a hangover after some alleged overtime in the office, or he'll be pampering himself for a liaison - and programme in some background noises of your own. You could download the noise of babies crying or a recorded message that says over and over again: "Dinner's ready, dinner's ready..."

Go out to a lap dancing club and take your mobile - and when he or she rings just let them hear some real background noises.

If all that fails, just get rid of him or her. Who wants to live with a lying toad, anyway?

Updated: 08:53 Tuesday, October 12, 2004