Using VMware's vSphere virtualization software, the managed hosting providers will allow customers to configure virtual servers over the Web and pay for the computing capacity they use on an hourly basis with a credit card, much as AWS does today.

The first companies that have signed up to offer the services, branded vCloud Express, are Terremark, Melbourne IT, BlueLock, Hosting.com and Logica. Those companies' services are in beta today or will be shortly, VMware said.

VMware CEO Paul Maritz introduced vCloud Express in his keynote at the start of VMworld Tuesday. The services are designed to let companies provision virtual server environments quickly and cheaply for test and development work, or to run applications that don't have stringent performance and security requirements.

"When you see the vCloud Express logo you know it means fast and cheap -- or rather I should say, fast and cost-effective," Maritz said.

Amazon has a long lead in the market for such services. VMware and its partners hope to attract customers by supporting a wider choice of operating systems and, in some cases, lower starting prices. Terremark's starts at less than US$0.04 per hour, for example, for a system with one virtual CPU and a half GB of memory. Amazon's pricing starts at $0.10 per CPU hour.