AFTER Big Brother, prepare to meet the rest of the family working for Voyeur TV. They want to lock you up in jail, cast you away on a desert island, put you on the bus you can't get off, test your fidelity to your partner - and even chain you to strangers.

Channel 4's peep show Big Brother ends tomorrow when the winner - Anna, Craig or Darren - walks out of the purpose-built house after ten weeks living in front of the cameras but that's not the end of the story. There's more of the same to come.

Broadcasters, spurred on by the success of a TV event that has gripped and bored the nation in equal measure, are scrambling to repeat the format after seeing the programme develop into a national talking point even among people not watching it.

Big Brother, named after the all-controlling head of state in George Orwell's novel 1984, stole poor Auntie's thunder. BBC1's Castaway 2000 came first, abandoning a bunch of ill-matched people on a remote Scottish island for a year. That was all but forgotten as the new show caught the nation's imagination.

There has been no escape from Big Brother over the past few months with the series helping Channel 4 achieve its highest audience share since the Hugh Grant film Four Weddings And A Funeral.

But the best figure of 6.87m is still way below soaps Coronation Street and EastEnders which regularly attract 14m viewers an episode. The week after Nasty Nick's departure, the most-watched episode was seen by fewer people than tired game show Catchphrase and repeats of Inspector Morse, The Vicar Of Dibley and Airport.

So not quite the ratings winner the PR people would have us believe. But what helped foster this Brotherly love was the way the other media - newspapers, both tabloid and broadsheet, and rival TV stations - joined in, devoting masses of column inches to the exploits of contestants both inside the house and after their eviction. Rarely has a programme on a minority channel resulted in so many page one stories and inside spreads.

This news was usually more interesting than what was happening in the house because mostly nothing much was going on. The inmates got up, talked, cooked, sunbathed, carried out the week's task and that was it. This was the TV equivalent of watching paint dry. Even worse, they were people you wouldn't want to share a house with for a day, let alone ten weeks.

Channel 4's advance promises that anything could happen proved unfounded. Nude body painting, a few relatively chaste kisses and Thomas getting over excited giving Mel a massage didn't satisfy Peeping Tom expectations while the conversation rarely rose above the "are you a bum or breasts man?" level. When the most dramatic moment is a row over tactical voting, you know you're not in the presence of great TV drama.

The most fascinating aspect has been watching how those evicted coped with life back in the outside world. The winner's £70,000 prize money is peanuts compared to what the "losers" can earn as TV presenters, models or selling their stories. Nasty Nick was even paid £5,000 just to wear a logo-adorned jacket at a film premiere. Then there are free nights out on the back of their TV celebrity as they attempt to prolong their 15 minutes of fame.

Having exhausted the fly-on-the-wall documentary approach, producers had no option but to go one step further and follow participants around the clock. But Big Brother is as much about real life as an episode of Crossroads. These were not people thrown together under the same roof by fate. They were carefully chosen to offer something for everyone, from the lesbian ex-nun and the loud blonde who overdid the lip liner to the randy Scouser and quiet brooding Irishman.

Big Brother's selection process seemed based more on Blind Date criteria and exhibitionist tendencies than any desire to engineer a serious social experiment.

The difference to predecessors like Airport and Driving School is that Big Brother could be seen 24 hours a day on its website, although producers got cold feet and pulled the plug when things looked like turning violent.

Channel 4 can expect massive ratings for the final programmes which must leave the BBC feeling pretty depressed at the overshadowing of Castaway 2000. This seems a far more honest series. There's no cash prize, the three dozen castaways have a range of backgrounds and ages, and making them live together for a whole year makes the situation seem more valid.

It's certainly gentler than the US version Survivor, which had 16 contestants stripping off and eating rats after being stranded on a Malaysian island. Not that the BBC's castaways are finding Taransay a desert island paradise. Some have already quit.

Events also forced a change in the original plan of not showing how the castaways fared until they returned home at the end of the year. The BBC began screening regular updates after realising their ratings value.

Now Big Brother's little sisters are muscling in on the act all over the world. The formula for the shows remains the same, only the method of containment and location changes. Unlike Castaway 2000, there are cash prizes to be won.

Channel 5 has launched Jailbreak in which viewers can try to help ten inmates escape from prison. Like Big Brother, The Bus comes from Holland. Eleven strangers travel round Holland on a bus for 16 weeks sharing an 18ft bed on the top deck with viewers voting off their least favourite passengers.

The Mole (from Belgium and coming to Channel 5) sends ten strangers to different locations to carry out tasks. They must identify which one of them is the production company's mole trying to sabotage their efforts.

Some ideas have an air of desperation. Chains Of Love has four men shackled to one women who frees them one by one until she's left with the man of her dreams. In Temptation unmarried couples in long-term relationships have their faithfulness tested. And how about The Big Diet in which overweight contestants are locked in a house and compete to lose most weight?

There's a danger the entertainment could turn as nasty as Big Brother's Nick. He shrugged off displeasure at his dirty tricks claiming, "It's only a game show". Clearly that wasn't the feeling of the Swedish man who committed suicide after being voted off a reality series in his homeland.

No wonder there are real fears that the search for outrageous variations of real TV could lead to what an observer called "ever more titillating and dangerous programmes".

l The final Big Brother programmes are on Channel 4 at 8.30pm and 10.30pm tomorrow with an omnibus edition on Saturday at 10.35pm. Also Inside Big Brother (Saturday, 9pm) goes behind the scenes and The World Is Watching...Big Brother (Saturday, 10pm) looks at how the show works abroad.

l Castaway 2000 in on BBC1 on Sunday at 8.50pm, Monday at 8.40pm and Thursday (Sept 21) at 9.30pm.

l Jailbreak continues on Channel 5 every day except Saturday.