  We investigate the feasibility of high performance scientific computation
using cloud computers as an alternative to traditional computational tools. The
availability of these large, virtualized pools of compute resources raises the
possibility of a new compute paradigm for scientific research with many
advantages. For research groups, cloud computing provides convenient access to
reliable, high performance clusters and storage, without the need to purchase
and maintain sophisticated hardware. For developers, virtualization allows
scientific codes to be optimized and pre-installed on machine images,
facilitating control over the computational environment. Preliminary tests are
presented for serial and parallelized versions of the widely used x-ray
spectroscopy and electronic structure code FEFF on the Amazon Elastic Compute
Cloud, including CPU and network performance.
