Szpiro, George G. The secret life of numbers: 50 easy pieces on how mathematicians work and think. Washington, D.C.: Joseph Henry Press, 2006. ISBN 0-309-09658-8.

Summary: Short essays, mostly biographical, historical, or related to current events, about mathematicians and technologists, for a non-technical audience. Much of the material was very familiar, but I enjoyed seeing some of the themes again anyway (fractals, the paradoxes of voting, the argument that Tetris is NP-complete).