My Lamborghini laptop has a pair of solid state drives that hold a lot of digital media from my work in Creative Suite. I don't want to pay to back these up to a cloud service, but I would like to preserve them somehow. Since solid state drives can just up and die on you and there's no magnetic media to recover, I was becoming more and more concerned about losing everything in a disk failure.
This morning, I clicked around the Interweb Tubes and came across Microsoft SyncToy. Just why it's called "Toy" is beyond me, but the thing does the job. You create folder pair associations and the thing will synchronize the files in those folders, either bidirectionally or just one way. I just ran it and it seems to work as advertised.
I'm keeping a secondary, backup folder of my work on the slave drive just in case the primary drive croaks. As far as I can tell, you have to run SyncToy manually, but that's fine. I know when I've made significant changes to my projects and my natural paranoia will ensure that I sync the folders then.
Regular readers know I'm no fan of Microsoft, but this is one tool I can recommend for sure.