Dropbox is probably the current leader in the storage application and service space for desktop users. Featuring an auto-commit-and-update mechanism to transparently send updates to the repository, changes are reflected on any other machine in near real-time.
Unfortunately, while Dropbox promises security, you cannot use your own infrastructure for data storage. Most data security policies would make this a show stopper for many organisations that wish to deploy such a facility.
By gluing a few existing open source tools together, you can replicate the functionality with a version control system, a file system watcher and a scheduled task.
18th–23rd January 2010