The T815 has just a bit more features than the T805 -- but both fit in your pocket, have visual and spoken directions and points-of-interest location (like the hole-in-the-wall burger joint).
The 2011 Index of Economic Freedom, which is a joint project of The Heritage Foundation and The Wall Street Journal, ranked 183 countries based on 10 measures that evaluate such things as openness to trade and investment, government size, fiscal soundness, business and labor regulation, property rights, corruption, monetary stability and financial competition and transparency.