How Porn Conquered The World (five); Blizzard: Race To The Pole (BBC2); Turn Back Time (BBC2):

Danni ASHE was described as being "way out in front by a mile" in the pornography industry.

This wasn't a reference to the size of her natural attributes but her exposure on the Internet.

Since February 1996, six images of Danni have been downloaded every second. That's an amazing figure which can be said of many performers in the industry considered in How Porn Conquered The World.

This documentary would have been easier to accept as a serious look at the spread of porn if the talking heads hadn't been interrupted by clips from sex films. Porn stars at least know they'll be required to expose flesh.

One intrepid adventurer recreating the race between Scott and Amundsen to the South Pole in Blizzard couldn't have imagined baring his bottom on national television. But Mark had a boil on his bum, so there he was with his underpants pulled down and medical men poking and prodding the boil.

I'd have been more worried about frostbite on my extremities than the pain of someone sticking a sharp object in my bum. The medic agreed. "Ideally we numb it, put the scalpel in properly, get out the pus, pack it, dress it. But if we're going to do that we should do in a tent," he said.

Back in silicone valley and the porn industry, we learnt how technology enabled the growth of pornography into the global big business it is today. The first videos, CD-roms and DVD all featured porn.

And the worldwide web, as Danni Ashe will tell you, has made porn more accessible. She's one of the women empowered by the new technology - an adult performer who set up her own website and took her future into her own hands, so to speak. Now they call her "the billion download woman".

Every since photography began, there's been pornography. A parallel smut industry runs alongside the mainstream film-making business in Hollywood. Now anyone with a camera can do it themselves, something customers watching porn have been doing for years.

These days anything goes, so how odd to recall that 26 years ago the Monty Python team weren't allowed to use the word masturbation in a sketch. The BBC allowed a reference to strangling animals but not to a nationwide hobby.

Guest Terry Jones also recalled that at one time there were only four films banned in Ireland and he'd directed three of them.

Turn Back Time offered him the opportunity to recall moments in his life when perhaps he'd made the wrong choice. This isn't some deep moral discussion but a variation on the Room 101 formula. Presenter Dara O'Brian and his guest mull over old times, aided by clips and quips.

One film Jones directed that wasn't banned in Ireland was Wind In The Willows. The programme re-edited the trailer to look like a porn movie called Mr Toad's Wild Ride. Amusing maybe, but I doubt it would record as many hits as Danni Ashe.