The latest edition of Xandros Desktop is downloadable at no charge from the Xandros website.
The package includes an office suite, e-mail client and multimedia capabilities. The operating system can be installed with a dual-boot option to run alongside other operating systems.
The company has aspirations to win business from Microsoft. "Open computing is coming of age and every desktop user should know that there is a full-featured Windows alternative out there," said Xandros chief executive Frederick Berenstein.
The software is distributed through an Open Circulation Edition licence, which means users can install the software for their personal use and pass it on through download mirror sites or by copying the installation CD.
A version for business, called Xandros Desktop OS Version 2 Business Edition is priced at £70. This version is designed to support desktop computer users who require authentication for a Windows-based network. The package includes a full version of Codeweavers Crossover Office and Sun Staroffice 7.