Explaining Riemann

Barry Mazur and William Stein are working on a volume entitled "Primes" to explain the Riemann Hypothesis to a larger audience. A working (very lay-friendly) draft of it is available for free download here!:

http://modular.math.washington.edu/rh/

On the same page, you can also view an hour-long Fora/TV talk of Mazur explaining, how to go about explaining the RH.