I cannot praise this versatile little free* program more. I have given up on personal RAID. I can't afford RAID 5, which is the only RAID I might feel assurance from. I started playing with the original consumer Promise cards and dealt with the headaches. Even the Medea RAID 5 units I used at work became a hassle. I learned the hard way not to trust these plug-and-play RAID 1 units offered by LaCie and the like.
I had one where the controller circuitry failed, but both internal drives (and ostensibly the data on them) were intact... But they were housed in an proprietary format, so I had no way to get the data off even if i pulled the drives out. I sent it back to LaCie and even though they noted that it was just the controller they replaced, they still nicely formatted the volume, destroying all data.
I have since taken too keeping two physical drives of the same size in separate enclosures and have them incrementally update one to the other nightly. The app I use to do this is GoodSync (Win/Mac). It's really low-profile/low-overhead and very configurable. My nightly updates are just a simple A->B incremental job. But I also have a job that connects to my colo server via SFTP as a midpoint, effectively allowing me to run my own Dropbox-style file locker. For this it has the ability to handshake with the server whenever any file changes in the specified local folder. I then run the client on multiple machines.
Additionally it has ability to work with commercial cloud services, such as Azure and Amazon, but I haven't tried those.
*There is a pay-version, but I haven't found anything yet that I couldn't do with the free version.