Dahlia Waingort

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Australia may be one of the most internet-connected countries on earth, with a super-fast broadband network on the way. But now the experts are warning there's danger with cyber crooks roaming the super highway.

Twins Anne and Helen were 20 years old when they learned they had been conceived from an anonymous man's sperm. They spent the next 20 trying to crack the mystery of his identity. Can a balance be struck between the rights of children and donor fathers?

On September 11 2001, thousands of dead were unaccounted for in the smouldering rubble of the World Trade Centre. Among them, was the remains of Mohamed Atta, whose last murderous act tipped the world into a confrontation between Islam and the West.

It's almost as hard to get into Supermax as it is to get out. This 21st century jail-within-a-jail is exclusively reserved for the most sinister of criminals.

Across the world, coral reefs are turning into marine deserts. It's estimated that more than a quarter have been lost and that 40 per cent could be gone by 2010. It's almost unthinkable that Australia's Great Barrier Reef could be headed the same way.

Milk, as natural and wholesome as motherhood, packed with proteins, vitamins and minerals, great for you and the kids. That's the image but just how beneficial is it?

Billions of dollars are fed each year into a nationwide prison boom that's seen the captive population nearly double in a decade. But could there be a relatively cheap and cost-effective way to stop prisoners reoffending?

Does a woman with the mental age of a two-year-old have the right to bear a child? Or should she be stopped - for her own protection and that of the potential child?

To its backers, Woomera played a humane yet crucial role in housing the growing numbers of boat people landing on Australia's shores. To its critics, this heavily guarded cluster of buildings, represented the dead heart of asylum-seeker policy.

Each week more than a thousand Australians are delivered the cruel diagnosis: they have dementia - incurable, untreatable, terminal. This episode of Four Corners chronicles the undeniable sadness of the descent into dementia.

Children across Australia talk about the alarming impact of bullying on their lives.