The Dutch have similar problems, but it's all about to c hange. They are set to change the country's road tax system by charging according to the vehicle type, actual usage, time of use and roads the vehicle is using. Using state of the art GPS equipment hooked up to a farm of computers, every vehicle will be tracked and a fee will be calculated based on usage.
For example, driving through a congested area at 5pm, when you can catch a train home, is going to cost you more than driving in a rural area where, arguably, cars are a necessity.
The revolutionary system will go live for freight transport in 2011 and be mandatory in cars by 2012. The Dutch government recently announced that there is simply no more room to build more roads, so this new scheme is set to reduce CO2 emissions and congestion.
The obvious problem is privacy, having your car tracked 24//7 may be good if it gets stolen, but not so handy if you're big on personal privacy. The founders however, disagree, arguing that the information collected will be deleted once a fee is calculated.
The Neatherlands is a relatively small country in comparison to Australia, so the system may be a little harder to implement here, but never say never.