Corel has released a free public beta of WordPerfect Lightning, a word processor that blends a desktop-based application with online collaboration and storage features.

WordPerfect Lightning has a ‘Notes’ tool to save text and images from the internet, in addition to a ‘Viewer’ that can handle PDFs, WordPerfect and Microsoft's Word documents. It also has a ‘Navigator’ to organise files.

The desktop application is 20MB and is compatible with Microsoft's new Vista OS and XP, Corel said. Users get 200 MB of storage space to back up data such as emails, contacts, bookmarks and documents, in addition to a calendar and free email.

WordPerfect Lightning is one of a wave of applications integrating desktop applications with online features for greater access and easier collaboration. In March 2006, Google bought Upstartle, a company that created the online word processor Writely. Writely is now integrated into Google Docs and Spreadsheets.

Free offerings such as Writely and WordPerfect Lightning are seen as a challenge to Microsoft's Office programs, which dominate productivity applications and brings the company much of its revenue.