Greg Dixon: On-demand TV is here already

I have never understood all the talk that the exciting future of TV is having programmes on-demand. Apparently in this thrilling brave new world, Homo Couchpotatous will simply push a button - though given the complexity of remotes now I actually doubt it will be simple - and in mere seconds order up any damn rubbish he or she wants any damn time he or she wants.

Miss Popularity, morning, noon and night. Pish, big deal.

I'd have thought that one of the best things about having a television right now is that you can plug a DVD player into it. And the best thing about a DVD player is that it plays DVDs. This obviously makes it a major advance on the VHS player, which could only play VHS tapes.

Anyway, what I mean is that, within reason, you can already have anything you damn well please on-demand morning, noon and night - as long as you are prepared to leave your house to get it. Leaving the house, I'm sure you'll agree, is actually a good thing.

Leaving the house has recently allowed me to have on-demand three of the most thoughtful and absorbing documentaries I've seen in some time - The Fog Of War, a terrific, curious interview with Vietnam War-era US Secretary of Defence Robert McNamara; the terrific near-death-in-mountains doco Into The Void (winner of a Bafta for best British film); and the terrific, tragic Capturing The Friedmans, a documentary on the destruction of a family by child-sex allegations.

Network television doesn't seem interested in playing this sort of thing. Perhaps there's no demand. But very occasionally its documentary strands throw up something unexpected.

Louis Theroux's small, peculiar show which started on Prime this week is certainly not in the same planetary system as Into The Void or The Friedmans. But the first episode, Louis And The Nazis, was the sort of thing I'd leave the house for if it wasn't already on.

Theroux, son of travel writer Paul, has one of the oddest interviewing styles I've ever seen.

The show included following around Tom Metzger, "the most dangerous racist in America", attending a skinhead rally and visiting a mother who lets her 11-year-old twins sing race hate songs. Theroux encountered and questioned each not only like they were from another planet (and indeed they seemed to be) but as though he was too.

It is, of course, all a pose. A few years back Theroux told Britain's Daily Telegraph that in his programmes he makes a virtue of being incompetent, of being bumbling.

"There's a tradition of writers doing that. It's what Woody Allen does in the cinema.

"It's not really done on television.

"What we've done with my programmes is create a fictional persona called Louis. I appear to be at the mercy of events, whereas, in fact, I am in control."

His shambling interview style sure as hell makes it entertaining - and it works.

His blank face and off-hand remarks woo his subjects into a false sense of security so they drop their defences.

And so you had the surreal, appalling sight of a mother and her young children singing along to their car's CD player: "They call me a Nazi and I'm proud of that, they call me racist and I shout it out loud ... "

Theroux's style is similar to the tiresome Ruby Wax's. But where she does no more than take the piss, there does seem to be a genuinely inquiring mind behind Theroux's amusing schtick.

Enough to save me having to leave the house on Tuesdays.