Does your cloud computing architecture plan for spikes in network traffic, and if so, how?

Every cloud engineer knows that there are peaks and troughs of network activity. Many engineers will architect systems to accommodate the peaks or spikes in network traffic. While this ensures that the resources will be available to every user who needs them, it also results in higher infrastructure and maintenance costs for the organization. A better strategy is to architect an IT environment to accommodate both average traffic loads as well as occasional and infrequent peak traffic. Cloud computing contributes to accommodating the traffic by providing the availability of standby systems. Your answer to the Amazon interviewer's question should demonstrate your knowledge of this, as well as the strategies you employ to accommodate spikes in traffic while maintaining a reasonable IT operating budget.