Some companies, however, stuck around, and others joined the service since the bubble. The service is now used by 1,400 organizations for training, meetings, conferences, and team-building, Linden Lab said. These include several companies beta-testing the enterprise software, such as IBM, Northrop Grumman, and Case Western Reserve University. Also, Chicago Children's Memorial Hospital uses Second Life for disaster preparedness training, and the University of Texas launched a year-long, state-wide initiative to use Second Life in the curriculum for all 16 campuses.

Second Life Enterprise users will be able to transfer virtual goods, such as buildings, clothes, and furniture, between the main, public grid and a Second Life Enterprise server. They won't, however, be able to move avatars between Second Life Enterprise servers and the public grid, so employees will need to keep a separate avatar for each service.

The new server provides standard tools for enterprise software, including LDAP support and backup and restore abilities. Avatars on Second Life Enterprise servers can have the users' real names, or any other names; in the public Second Life, in most cases, users have to pick between an approved list of surnames, and select a first name that isn't already in use in combination with the surname they've chosen.

Second Life Enterprise can support up to eight simultaneous virtual servers -- known in Second Life jargon as "islands" -- and users can customize the servers and store the customizations. So, for example, an island might be a virtual conference center one day, and a training area the next.

Second Life Enterprise can support up to about 700 avatars logged in simultaneously. It comes with a set of 10 business-ready default avatars, with different ethnicities and appearances.

In addition to enterprises, Linden Lab sees the new software as useful to service providers who could use the servers for multiple clients for training and Second Life events.

As part of the enterprise announcement, Linden Lab announced the Second Life Work Marketplace, to be launched in the first quarter, where developers can sell virtual merchandise such as clothing, furniture, building, and collaboration tools and tools for delivering presentations. Linden Lab will take a cut of the revenue from the marketplace.

Linden Lab is far and away the leader in non-game virtual worlds (World of Warcraft is also a virtual world). But it's a small market, and LInden Lab has competition from companies including Forterra Systems, ProtonMedia and Teleplace. Also, OpenSim is an open source Second Life clone, which IBM integrated into its Lotus Sametime collaboration software.

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