The open source support center at Fidelity Investments is humming. The organization, formed two years ago within the Fidelity Center for Applied Technology, is responsible for determining where - and how - open source software fits in the financial services giant's broad IT infrastructure.

Fidelity has been using Linux for years, so long that Charlie Brenner, senior vice president of FCAT in Boston, says the operating system is "part of the DNA here." What's of interest now, he says, is moving up the stack. "We would love to run fewer proprietary" applications.

The appeal of innovative, broadly tested, community-supported, low-cost software that provides the added incentive of sidestepping vendor lock-in is enticing more companies to take a look at what's available beyond Linux.

Open source tools such as Linux and the Apache Web server are considered the old guard, used in various ways in most enterprise data centers. But momentum is building around infrastructure applications such as the JBoss application server, databases such as MySQL and PostgreSQL, and security tools such as OpenSSL and Snort . Content management and collaboration tools also are getting a second look. CRM and ERP are emerging as open source alternatives, as is code for IP PBXs and other network gear.

Analysts say a growing number of enterprise users are turning to maturing open source tools. Gartner predicts that by 2008 open source software will compete with proprietary products in all software markets. By 2010, the Global 2000 will consider open source for 80% of their infrastructure investments and for a quarter of their business software needs. It's a dramatic change considering that last year open source was considered in fewer than 5% of business application decisions.

"The barriers [to open source] are falling away," says Mark Driver, a vice president and research analyst at Gartner. "Companies who would not have considered open source software in the past because they were worried about nightmare scenarios, now are saying, 'If we were successful with Linux, maybe we can be successful with databases, with content management.'"

Client requests for information regarding open source are "coming out of the woodwork," Driver says. Gartner will hold its first open source-focused conference in December.