Regarding Randall's post below, the reputation the Japanese have for long workdays and high productivity appears to be wildly exaggerated, or at least limited to a small subset of the population. Japan's PPP-adjusted per-capita GDP is on par with France and Spain, or about 25% below the US and Ireland. A small part of the gap can be explained by lower labor force participation among women (about 48% versus 58% in the US, according to this PDF), but not more than 3 to 4 percentage points. It's also not attributable to differences in age distributions, according to table 2.3 here.
As for those legendary long hours, the average Japanese worker worked about 1828 hours per year versus 1777 for Americans, or a difference of about 1 hour per week. The South Koreans, on the other hand, average 2390 hours per year--about 12 hours per week more than Americans.