In his article Grant Babcock says:

"The principle that the value of a currency can be traced back to a time when it was not yet a currency but just a commodity like any other is called the regression theorem, and interested parties can read more about it in Human Action Ch 17 § 4."

But he forgets to differentiate between intrinsic value and exchange value.

The intrinsic value might be zero (as is that of the USD), but the exchange value is much higher than zero, due to the specific properties of the bitcoin currency (anonimity, security, safety, traceability, non-inflatability etc...).
So yes, many times a currency starts as a commodity with non-zero value, but that's not an absolute requirement for a currency to be just that: a currency.

For instance, the intrinsic value of the USD started as a certain fixed amount of gold, then went to zero.
The property of it being backed by its artificial scarcity, caused by the requirement of all oil from the Middle East to be payed in USD, gives it a value as exchange currency.

Off topic:
That's also the reason why Saddam Hoessein and Khaddafi (and soon Hugo Chavez, and who knows, Iran) are/were/will be bombed into oblivion by the USA and its partners in crime, the NATO: they were going to accept payment in other than USD currencies.

Back on topic:
So, where intrinsic value is not needed, exchange value is, for a currency to be accepted as a means of exchange.

Not really.
As far is 'terrorism' is concerned, the USA is quite able to dictate its rules to the rest of the world.
Look at what they did with air travel.
And as the USA is ruled by the banks, it's clear which way regulation will be heading.

Remember what happened to Jesus? Also God-sent...

Expect a SWAT-team in your bitcoin exchange when it threatens to go main stream. 

Thank you!

Edit: I just finished ordering 2 of them XFX.

Thanks for clearing that up for me 

No, but he can order, and I wanted to know which one to order.

My supplier carries 6 brands of HD6990 card: ASUS, Club 3D, GIGABYTE, PowerColor, SAPPHIRE and XFX.
Now I remember ever having read a review of the 5970 card, and there it was stated that for instance AMD's reference design had issues with the VRM's coolings, and that ASUS and Club 3D just copied the reference, including that particular design flaw, but that Sapphire made its own improvements.
Does anybody know if this is general behaviour of these manufacturers and which manufacturer produces the best cards for mining?

Thanks

Oops, forget that, following the other link, then click on the 'forum' tab, brings me there. 

Ok, so I follow that link, then click on 'Jump to BitcoinVM' and get: "The forum you selected does not exist." 

Yeah, right! 
Following your steps, in my setup there is no /etc/X11/ , let alone a /etc/X11/xorg.conf .
But that doesn't matter, it seems to work: At startup the bitcoin window opened and an address (bitcoin account) was already generated.

That option 'generate bitcoins', does it use a possible graphics card, if available? (Let me guess: NO)

Wow, thanks for the update! I had already finished installing a tinycore linux in a KVM VM and was going to study the install process of bitcoin.
Now I will just follow your script and see what comes out.
Great! 

Oops sorry, I read past that passage where you said that instructions to set up our own are forthcoming.

Wow, very nice!
Do you have a list of instructions to set up an identical copy of this Tiny Core Linux Bitcoin client?
I would like to install one for my QEMU Virtual Machine Manager.
When finished, I can also upload a copy.

Do not underestimate the power of the banks, their political influence and the tenacity with which they will pursue their financial interests.
A few examples:
1. Gold is the enemy of central banks and what happened less than 100 years ago?
American government confiscated all the gold of the American citizens.
2. The Romanov Tsar didn't want a Rothschild central bank and what happened?
The 'Baron' orchestrated a Bolsjewik revolution and massacred the whole Romanov family.

If needed they will explode a nuclear bomb in the middle of Manhattan, with a sticker on it saying "Funded with money laundered through the bitcoin network and detonated by terrorists using the bitcoin network."
"Oh, and by the way, bitcoin is also used for illegal drugs transactions and child porn."
Watch how quickly the whole protocol will be killed by all ISPs around the world.
Except of course Venezuela, Libya, Iran, Syria and North-Korea.

@speeder : I thought the 'fine' was some kind of contribution to the retirement of the workers, as in my (very limited) knowledge participation in a retirement fund is not obligatory and seldom practiced. So instead of the employer constantly (i.e. monthly) putting money in a retirement fund, the employee gets it with his dismissal.

And re slavery, it even continued after the so called abolishment, and with happy participation of the Dutch who kept sending ships full of 'galinhas' to Bahia (or was is Ceara?), as I have understood it. The Dutch were the last to stop trading slaves. So much for christian mentality...

Even if the infrastructure will get limited to 'registered-only' services?
I hope you're right.
I very much support the ideals where bitcoin stands for, especially to take control out of the hand of the banks.
But man are they powerful...

No, crystal ball 

No, serious, I know it's difficult to draw a line between defeatism and realism, but I really consider this realism.
Governments and central banks just don't like initiatives like bitcoin, and history proves they will go to great lenghts to kill this kind of jokes. No offense.
I'm already feeling some premonition coming up along the lines of Gavin Andresen as a second Julian Assange.
If bitcoin is so well distributed, then why is Mr. Andresen so important? He shouldn't be.

The problem with bitcoin is that it competes with both banks as well as government.
Banks don't like it when the money creation and issuing is out of their hands, and governments don't like it when the circulation is beyond their control.
The Wörgl experiment ( http://en.wikipedia.org/wiki/Worgl ) and the, I think it's named Liberty Dollar (?), have shown that government will go full force (and that includes both army and FBI) after the 'criminals' who dare to operate an independent currency within a country.
No doubt bitcoin will share the same fate once it gets big enough, unfortunately.
And don't shout: "Internet is out of control of the goverment!" because it's not.
Obama has a 'kill switch' and other governments undoubtedly will implement such legislation first before cracking down on bitcoin.
Apart from the 'kill switch' there are deep packet inspection and end-user prosecution to bring dealing with bitcoins under government control.
ISPs become bigger and bigger, and will act more and more like government puppets in order to (and in that order):
1. not damage the carreer perspectives of their CEOs,
2. not damage the coporate profitability figures.
This way it will become quite easy and unavoidable that all internet connections will be regulated in a sense that they will be dissallowed unless allowed, contrary to the current situation in which they are practically all allowed, with here and there some exceptions like domain hijacking by the Dept. of Homeland Security (in cases of copyricht violations, for God's sake!).
Internet II is just around the corner, in which all traffic will go through some big providers, with internet IDs identifying the participants, and will be snooped upon by government, in order to protect the Homeland against 'terrorism', catastrophies 'and any other action deemed inappropriate' by The President.
So I'd say have fun with your bitcoins, but step out before government steps in.

Theoretically yes. The only problem is that it competes with both banks as well as government.
Banks don't like it when the money creation and issuing is out of their hands, and governments don't like it when the circulation is beyond their control.
The Wörgl experiment ( http://en.wikipedia.org/wiki/Worgl ) and the, I think it's named Liberty Dollar (?), have shown that government will go full force (and that includes both army and FBI) after the 'criminals' who dare to operate an independent currency within a country.
No doubt bitcoin will share the same fate once it gets big enough, unfortunately.
And don't shout: "Internet is out of control of the goverment!" because it's not.
Obama has a 'kill switch' and other governments undoubtedly will implement such legislation first before cracking down on bitcoin.
Apart from the 'kill switch' there are deep packet inspection and end-user prosecution to bring dealing with bitcoins under government control.
ISPs become bigger and bigger, and will act more and more like government puppets in order to (and in that order):
1. not damage the carreer perspectives of their CEOs,
2. not damage the coporate profitability figures.
This way it will become quite easy and unavoidable that all internet connections will be regulated in a sense that they will be dissallowed unless allowed, contrary to the current situation in which they are practically all allowed, with here and there some exceptions like domain hijacking by the Dept. of Homeland Security (in cases of copyricht violations, for God's sake!).
Internet II is just around the corner, in which all traffic will go through some big providers, with internet IDs identifying the participants, and will be snooped upon by government, in order to protect the Homeland against 'terrorism', catastrophies 'and any other action deemed inappropriate' by The President.
So I'd say have fun with your bitcoins, but step out before government steps in.

I would surely stay on the southern hemisphere as all most of the nuclear weapons are located on and pointing at locations on the northern hemisphere. The nice thing about the southern hemisphere (apart from the fact that there is that beautiful country Brazil! Que saudades!) is that northern and southern hemisphere are separated by the equator, which acts as a screen between northern and southern air currents.
You must have gotten the point already: in case of a nuclear war (and the USA has no more money for a conventional one, so nuclear is the cheapest next option) you should be much safer on the southern, than on the northern hemisphere.

As soon as you see all kinds of royalty and Goldman Sachs CEOs going on 'holiday' somewhere far south, then you'll know it's the time

Anyway, if I were you (or any Brazilian citizen) I wouldn't leave Brazil if I had a decent income there...