Best-known for its Quicken line of personal finance software, the Mountain View, Calif.-based vendor has carved out a tidy business with QuickBase since its first release in 2001. QuickBase is used by several thousand companies, including 43 of the Fortune 100, mostly at the department or workgroup level to enhance workflow and share data among remote workers, according to Intuit.

Those features were relatively rare when QuickBase was first released. But in February, Microsoft released Office Live, a set of hosted collaboration applications based on SharePoint, its collaboration server, aimed at small businesses. It is also readying new versions of enterprise software such as SharePoint and InfoPath, which let users create XML-based forms.

"Intuit has done a pretty good job of migrating some of its user base onto the Web," said Paul DeGroot, an analyst at Directions on Microsoft, a Kirkland, Wash.-based consulting firm. "Microsoft clearly can't ignore this area."

In addition, Web-focused companies like Google Inc., with its Google Spreadsheets and Writely beta applications, and smaller start-ups have released a raft of Web-based applications that mimic Office applications and provide Internet-based collaboration.

So far, neither Microsoft's nor other vendors' offerings have tempted Anne Walsh, a database administrator at Genworth Financial Inc. who has used QuickBase for five years. About 250 employees in her division, which sells insurance for long-term care, use QuickBase for sharing documents and keeping track of processes.