Downloading Xero unknown from the developer's website was possible when we last checked. We cannot confirm if there is a free download of this software available. This software is a product of Xero. We recommend checking the downloaded files with any free antivirus.
From the developer:
Xero is an award-winning online accounting software for small scale businesses. Xero offers a variety of features to make your business function smoothly and efficiently. The software handles all the accounting transactions effectively. It permits unlimited users to get online at a time and work in collaboration over data which is accessible through a single ledger.
You may want to check out more software, such as Xero Conditioner, TimeCamp or CSV2OFX, which might be related to Xero.