Sloane's Gap.
arxiv.org
arxiv.org
Very good video on Sloane's Gap, for the impatient: http://www.youtube.com/watch?v=_YysNM2JoFo
The article is particularly interesting to me for it's examination of what complexity theory tells us to expect for the distribution of 'interesting' integer sequences.
That cultural influences can (probably) have such a dramatic and measurable effect on something like mathematics is fascinating as well.