Amazon Web Services introduced a fully managed, secure document storage and sharing service for the enterprise.
Amazon Zocalo is a cloud storage service that lets users selectively share it with others (inside or outside of their organization), solicit feedback, manage versions and track deadlines.
A Zocalo client application on the desktop/laptop is used to sync files in a designated folder. AWS initially is supporting Windows 7 and MacOS (version 10.7 or later). Pricing start at $5 per user per month, including 200 GB of storage. A limited preview is underway.
https://aws.amazon.com/zocalo/