Electricity bills of large-scale Internet services are a major component in overall operating costs. As a result, it is increasingly important to identify cost-reduction approaches, either through reducing energy consumption or by strategically avoiding periods or data centers with the highest electricity costs. The first group of approaches based on reduction of energy consumption has been explored for many years. However, approaches that exploit various types of electricity price variability have been recently proposed. There is a need for a holistic optimization framework to explore various strategies to mitigate exposure to price variation.