Optimizing Traffic in Virtual and Real Space
  We show how optimization methods from economics known as portfolio strategies can be used for minimizing download times in the Internet and travel times in freeway traffic. While for Internet traffic, there is an optimal restart frequency for requesting data, freeway traffic can be optimized by a small percentage of vehicles coming from on-ramps. Interestingly, the portfolio strategies can decrease the average waiting or travel times, respectively, as well as their standard deviation (``risk''). In general, portfolio strategies are applicable to systems, in which the distribution of the quantity to be optimized is broad. 
Dirk Helbing, Bernardo A. Huberman, and Sebastian M. Maurer