Benford’s Law: This is fascinating:
Benford’s law, also called the first-digit law, states that in lists of numbers from many (but not all) real-life sources of data, the leading digit is distributed in a specific, non-uniform way. According to this law, the first digit is 1 about 30% of the time, and larger digits occur as the leading digit with lower and lower frequency, to the point where 9 as a first digit occurs less than 5% of the time. This distribution of first digits is the same as the widths of gridlines on the logarithmic scale.
You can test it at the aptly-named testingbenfordslaw.com. This article has more on it, including the results of a paper that tested EU economic numbers against Benford’s Law. The most suspicious numbers? Greece’s economic output over the last decade.