On the one hand, there's research that purports to show a lack of correlation between IQ and accumulated wealth. On the other hand, there's research that purports to show a positive correlation between IQ and the ability to make good investment decisions (earlier discussed here).
For some odd reason, the first research appears to be going around the blogsphere faster than the second had.
Maybe it's the cost of grad school that does it … Robin Hanson has a suggestion on saving money on grad school.
On the other hand, the Cognitive Reflection Test that's correlated with the ability to make good investment decisions is partly an IQ test and partly a patience test. It's possible that the IQ tests that showed a lack of correlation are partly IQ tests and partly impatience tests. (They might be timed tests without “trick questions.”)