Common day backup software suites and hardware devices fall primarily into two categories: Complete and archival. You're usually limited to a time-based backup routine or a backup of things changed. Usually that's enough, but anyone who has dealt with huge NAS clusters or restoring particulars from tapes knows the headache a backup can bring, especially with people who work from home. IBM wants to change this, for the better. 'Tivoli Continuous Protection' as it is called is designed to do real-time archiving as a file is modified, even with a remote or offline workstation. Think of it as sort of the emergency save feature modern office suites have, but with networking capabilities:
"IBM said the software works by first creating a local "within milliseconds." If connected to the Internet, the software also sends another copy to a remote server for safekeeping."
The package launches in the the middle of October, and is really oriented for businesses rather than users. However, like many technologies that start off like this, a home version will likely surface soon in some form. One day, perhaps, data loss will be a thing of the past.