Rhosty, your proposed tax would be far more of a handbrake on the economy than the existing taxes. It would also be easier to dodge, as people would just use cash.

Ross Garnaut should comment on this article.
Is it possible to draw his attention to OLO?
Australia's economic security is at stake.

All other posters have failed to realise the seriousness of the problem and the need for an innovative solution.

What we need is a voluntary tax on sex. Each resident who reaches the age of 18 would have to decide whether or not they wish to have sex in the coming year. If thay wish to have sex, they should buy a sex licence, costing $5,000; if they do not wish to have sex they should buy a virgin permit, also costing $5000. Residents would be free to switch between the two any number of times they wish during the year.

Purchase of a sex licence/virgin permit would remain completely voluntary. However a woman without a valid virgin permit could not prosecute a charge of rape, and any man who comes closer than 10 metres to any woman without a valid sex licence would be subject to six months imprisonment.

In order to be non-discriminatory, the fee would be the same for all without regard to age, sex or income.

Based on current census figures this proposal could raise over $70 billion per year.

Oh thanks for commenting there Ross.
A tax on sex.
That's another brilliant idea, like the one taxing CO2!

Thanks Ross Garnaut for that contribution. At least it's got more chance of working than the one you recommended to the Labor-Greens government to tax the unmeasurable emissions of CO2 !. And they were incompetent enough to trust you so they legislated it. Just like pink Bat, BER, And a host of other green nonsense that is costing us $20 billion per year for absolutely no beneficial change to the climate or sea levels.!

People could just use cash!
Well that would work well in a cashless economy, or international bank transfers/remittances, I don't think!
We who own the printing presses, could very easily and regularly change the color of money, and as simple as changing the ink.
And then giving the public just several weeks to come in and exchange their soon to be worthless cash, with a new issue that still is!
Those coming in with huge bundles of (dog eared) cash, would automatically trigger a response, and some very awkward questions, plus some ongoing future surveillance, to ascertain whether they're part of the legitimate economy?
Even then, without a tax number and adequate evidential income and taxation records, may find they cannot exchange their money, or pay double tax, (income and GST) on their surrendered/exchanged money, as the least of their worries!
And significant rewards could be offered, in order to expose the black economy/criminal activity!
Even the Mafia, very sensibly paid tax, so as to avoid too much investigation, or jail terms for tax avoidance!
Those that cheat this way, still send their kids to publicly funded schools/hospitals, drive on publicly funded roads, and collect benefits/pensions etc; that the honest taxpayer pays for!
And who no doubt, would take considerable pleasure in exposing these (thick as a couple of bricks) cheats!
Particularly if they could earn a tidy sum as reward, for having exposed any tax cheat!?
Also, those people who hold too much cash about their person, at home or in their business premises, always risk robbery, that could include serious assault, and maybe even the death of a loved one.
In the final analysis, we are just a few years away from biometric supported smart cards and a cashless economy.
Rhrosty.