Quoting from workspace news:

The STAR community successfully completed its first production-size deployment of a VM-based virtual cluster managed by the workspace service and backed by EC2 resources.

The 100 node cluster was composed of a headnode and workernodes based on the OSG 0.6.0 grid middleware stack and Torque. Its deployment-time configuration was securely coordinated by the new workspace contextualization technology.

[UPDATE, related: virtual-cluster-appliances]

[UPDATE, see: One-click clusters, VWS TP1.3.3]