MagLev is only marginally faster than any of the current crop of high speed trains (HSTs) (MagLev's current record is 581 km/h compared with TGV's record of 575 km/h) and is significantly more expensive to build.
However, MagLev's ability to operate reliably and with low on-going maintenance far exceeds that of the HSTs. As the Wikipedia article notes, "with conventional railway trains, at very high speeds, the wear and tear from friction along with the concentrated pounding from wheels on rails accelerate equipment deterioration and prevent mechanically-based train systems from achieving a maglev-based train system's high level of performance and low levels of maintenance. Indeed, it was concerns about maintenance and safety that convinced Chinese authorities to announce a slowing down of all new conventional high-speed trains to 300 km/h".
Of course both high speed rail and MagLev need a track to run on, but at least MagLev is amenable to elevated construction.
The big problem with both of these technologies, and the reason they require more and more energy to go faster and faster is the air through which they travel. The quicker the vehicle moves, the greater the air resistance. Worse, the force needed to work against the air increases exponentially with the speed.
This is done by constructing a metal tube of less than 2m diameter in which small 'cars' able to easily carry six passengers ride. The tubes are completely sealed and have all air removed. Effectively, the passengers are travelling through space. Most implementation plans include two tubes (either beside or above each other) to facilitate travel in opposite directions.
There are other proposals which consider even larger tubes in which a 'bus' might fit, or even large shipping containers.
The big, nay huge, advantage is that without air resistance the cars may be accelerated to very high speed (over 6,400 km/h) and once moving will need very little (if any) further energy to keep moving.
Even better, decelerating the cars will actually regain most of the energy for re-use.
At 6,400 km/h no two places on the Earth are more that 3 hours 10 minutes apart and in fact the journey from Sydney to Melbourne would probably take no more than 15 minutes.
Clearly, this is a relatively simple system for land-based transport, but what of trans-ocean? Proponents are suggesting a sub-sea tube mounting that will keep the ETT 45m to 90m below sea level; well below any shipping or storm influence.
The system was developed by Daryl Oster in the early 1990s, with a patent application in 1997.
So, what of the practicalities?
The installation consists of two 2m diameter tubes mounted on posts (perhaps) 5m above the ground. At each end is a terminus with a store of ready-to-use cars and an air-lock.
Bookings are probably not necessary as cars will depart every 20 seconds; just pay and go.
In Sydney, the car is filled with passengers and their luggage and then sealed. The car is then moved into an air lock mounted to the side of the tube. Once sealed, the air lock is evacuated of all air and when ready, the separation is opened and the car is inserted into the main tube.
A linear motor (also known as a MagLev) accelerates the car at 1G, reaching full speed in around 650 seconds (a little under 11 minutes), by which time it has already travelled over 600km.
Around 600km from Perth, the MagLev engages the car as a generator and recovers almost all of the energy as it decelerates (also at 1G) to rest at the terminus. The car is shunted into an air lock, which is filled with air immediately after the tube door is closed. Soon after, the car emerges into daylight and the passengers disembark. A total of 40 minutes travel time.
Of course a simple point-to-point service is of little use; we need to establish a full mesh service. Hint - Melbournites really don't want to travel to Sydney in order to get to Perth. This means there must be a means of merging and diverging tubes.
In addition, there are hills - so a means of accelerating the car up and then recovering the energy on the down is required. Nothing difficult there.
Estimates suggest that a fully operating system will cost around one tenth of an equivalent highway (not including fuel and other costs) and around one quarter of a high speed rail system. And of course ETT has considerably lower maintenance costs than either and due to deceleration energy recovery is exceedingly cheap to run.
Are there disadvantages? Of course there are.
Furthermore (and more benignly) the ability to rapidly respond to air leaks would be crucial to the profitable operation of the system, although a combination of air pressure detectors (they should stay at 'zero') and speed detectors (trains shouldn't slow down in a vacuum) will be sufficient to identify such problems. The repair may not be as quick though.
What of the travelling public? Would they enjoy travelling in a windowless 'bullet' inside a sealed tube? It would be hoped that the speed gains would more than compensate for the loss of a window seat.
After-all, the standard commercial airline flight from Singapore to London currently takes up more than six movies - imagine only getting half-way through the second as you arrive? In addition, there would never be any turbulence - the ride would be feather-smooth the whole way.
Currently, there are planned implementations in China but none has yet been built, and with Australia's long-term fascination with the never-profitable high-speed rail, this could form a very useful alternative.