IBM said it's planning to launch a global, online marketplace for software applications under a plan it's calling the Blue Business Platform.

The marketplace will feature a mix of business applications and services aimed primarily at small- and mid-sized companies, IBM announced Thursday at a conference in Los Angeles for its business partners.

IBM said it believes that the Web-based model will allow it to tap smaller companies around the world, which it says represent a $500 billion IT market that it has trouble serving profitably through traditionally sales channels.

IBM said the marketplace will offer pre-integrated products and services from IBM and independent software developers. Customers will be able to use the software they buy "on premises or in the cloud," IBM CEO Sam Palmisano said Thursday during an address.

Palmisano also revealed Thursday that IBM is working with Google to build a worldwide network of connected servers, an architecture sometimes referred to as a computing cloud, from which it plans to deliver software and services.

The online store will be organized geographically and also by industry. Customers will be able to purchase software or services in just four clicks, IBM said. The company plans to pilot the marketplace throughout 2008. It did not say when it plans to formally launch the service.

IBM on Thursday also unveiled a new server for small businesses.

The Lotus Foundations Start server includes Lotus Notes and Domino for e-mail and collaboration, as well as security, backup and recovery features. It's aimed at SMBs with little or no IT support and it can be deployed in as little as 30 minutes, according to IBM.