Datamation's Jeff Vance has assembled a list of "10 Hot Cloud Computing Startups for 2010." Making the grade on the security front are:

Altor Networks

What they do: The rapid adoption of virtualization technologies signals a major transition in the datacenter. Enterprises are achieving major benefits, including operational cost savings, consolidation of physical servers, and greatly streamlined deployment. However, understanding and locking down the security posture of virtualized datacenter infrastructures represents a significant challenge.

Altor tackles this challenge through a virtual firewall/IPS system that mitigates risks to virtualized and cloud-based applications and data.

Customers: Altor has 25+ customers, including Syracuse University, the U.S. Army, International Medical Corps, Ericsson and Nielsen Mobile.

Funding: $7.5 million in Series A and seed funding from Accel Partners and Foundation Capital.

CEO Amir Ben-Efraim was formerly head of business development at Check Point Software.

Headquarters: Redwood Shores, CA.

Lookout

What they do: Smartphone security, or rather lack thereof, is a disaster waiting to happen. Anyone who has seen PCs bog down when a bloated security suite runs knows that porting desktop-style security to the smartphone is a mistake.

Lookout’s approach is to combine two emerging technologies: smartphones and the cloud. A lightweight client communicates with cloud-based services to offer AV/firewall/ IPS protection, data backup and device lookdown/remote wiping if the handset is lost or stolen.

For any industry observers, one of the cloud’s biggest selling points is its potential to transform the mobile Internet. In order for the mobile platform to be truly enterprise-class, though, you can’t skimp on security.

Customers: For now, Lookout is a consumer, rather than enterprise security service. Currently, the beta version is free, although Lookout plans to charge a subscription fee in the future. Lookout also intends to release an enterprise version late this year or early next.

Don’t be surprise if Lookout or a startup like it follows the trail blazed by major PC security vendors and starts selling to the pipe providers, rather than consumers. It’s in the carriers’ interest to protect their networks by offering security as a free service to their own subscribers.

Funding: $5.5 million in Series A funding from Khosla Ventures, Trilogy Partnership and angel investors.

John Hering, CEO, founded Lookout (formerly Flexilis) with CTO Kevin Mahaffey in 2005. The two met as students at USC.

Headquarters: San Francisco, CA

To view the full list, click here.