The BBC seems to have an affinity for mathematics documentaries at the moment. As well as re-airing The Story of Maths, they are also currently running a three-part documentary, The Code.
The programme highlights of mathematics popping up in unlikely places in nature. For example, one particular species of cicadas emerges only once every 13 years, in order to minimise their chances of coinciding with another species. This works because 13 is prime and therefore shares few factors (only 1 and 13) with other numbers.
There's also a "treasure hunt" based on clues from the TV show, the online games and the blog: Treasure Hunt
Catch the final episode on Tuesday 10th at 9pm, or view the whole series on BBC iPlayer.