Wikipedia
LazySave
LazySave is a proprietary backup software for Windows first released in 1998.
LazySave is a screensaver. It provides a feature rich interface enabling Duplication, Differential and Version Control backups. The latest version adds the ability to create a new folder each day if required. Most backup software is configured to run at specific times and so can be annoying if it slows down your computer. LazySave runs on your computer when you are not there, as it is a screensaver. As a consequence, the time between your files changing and your files being backed up, is minimised.