[Arthalion]

Replicators are like free energy -- they are simply too dangerous to an economy to allow to exist.

Yes and no. Capitalism is good for us today simply because there isn't an alternative. We exist in a world today where various people control various limited resources (natural or produced) and they exchange those resources with others who are in need of them. There are three possible ways to do this: Barter, in which you directly exchange goods with another, but which fails when you need goods from another and he doesn't want yours. Communism, which takes resources from all and distributes them, but which fails because it removes the incentive to produce. Capitalism, which is essentially barter with a recognized third party exchange medium (currency), but which fails when you don't have any of that medium. The free world has decided that capitalism is the superior choice, because it's downside can be overcome with hard work, and because it imparts few restrictions on the rights of those involved with it.

The Star Trek universe turns the whole situation on its ear...they aren't capitalist, socialist or communist. The basic tenets of the economy, that there are limited goods to be exchanged, has been eliminated by the invention of unlimited production capacity (through robotics), unlimited energy (through antimatter reactors), unlimited resources (through replicators), and unlimited land (through planetary colonization enabled by high speed spaceflight). There are very few limited resources remaining to be traded, so all three common forms of exchange basically pass into history. This isn't neccesarily a bad thing...everyone can own a home, everyone will have unlimited food, and everyone can do what they want with their lives. Unlike communism, the Star Trek universe doesn't take away from others to create a utopian environment, it exists in an environment devoid of want.

Think about it this way: If you had $50 billion dollars sitting in the bank, what would you be doing right now? What would you be doing tomorrow? Next week? Whatever you answer, it basically boils down to "Whatever I want to do", whether that's working or sunning on a beach in Bora Bora. In the Trek universe, mankind has reached the point where everyone can make that choice. It may seem like a foreign concept to most people used to our current economic situation, but it really wouldn't be a bad thing IMO.

[Sofa King]

What about services? Robotics can't do everything. And no form of energy is completely free. Physics allows no such convenience.

[Junior]

That sounds all well and good -- until you realize it's the government that controls everything. One can't simply "have a house;" one has to go to the government to give you the house. No one appears to own any form of personal transportation, which means the government controls the movements of the people.

The people of the Federation may be free of want, but they are not truly free.