> Russia with a 13% flat tax

That's a common misconception. Yes, personal tax rate is 13%, but your employer will have to pay for health insurance (5.1), social services (2.9), and pension fund (22). Overall, you get closer to 43% flat tax rate.

The big difference is - you never see these moneys in the first place. Your paycheck is a net pay, all deducts are applied by the accounting department and only 13% rate is widely advertised as one the lowest in the world.