http://en.wikipedia.org/wiki/Estonia
Estonia (relatively) recently adopted policies supported by Milton Friedman. Along with that and being freed from the USSR, Estonia's economy is growing rapidly. Estonia adopted a flat tax rate that has been decreasing steadily over time. Estonia has extremely low public debt, free trade, a budget surplus, and had, in 2011, 5x the GDP growth of other EU countries (although they recently adopted the euro :( ). Estonia is doing quite well compared to the rest of the EU, despite all their damn economic freedom.
Regardless, how is "not many have tried it, therefore it doesn't work" an argument? On the other hand, one doesn't have to look very far back in history to see where too much government involvement into the economy (and therefore every day life) leads.