From World Politics Review, Bulgaria is intending on adopting a 10% flat tax rate. This is a huge win for libertarians like myself. From the article:
Since Estonia adopted a flat tax rate in 1994, enjoying very robust GDP growth ever since, Eastern European countries have been gradually warming to this system that promises to attract foreign direct investment, increase transparency, and drastically curb tax evasion. Slovakia, Romania, Albania and many former Soviet republics have all adopted a flat tax.
Now it's Bulgaria's turn: yesterday, the government declared it will introduce a flat tax rate on personal income. At 10 percent, Bulgaria's flat tax rate will be among the lowest in the world, down from a tax rate that currently ranges between 20 and 24 percent.
Other countries with a flat tax regime are Macedonia, Ukraine, Mauritius, Mongolia and Russia.
Experience from countries that have adopted the flat tax has, in many cases, shown it to be a boon to economic growth. If only the Western nations, with their bloated welfare systems, massive military spending, large scale subsidization of inefficient industries and high taxation rates could learn from this.