Allway sync (Score 1)

I've found Allway sync (http://allwaysync.com/) to be a bulletproof multi-directional sync tool, which I regularly use to synchronize 100's of GB of photos, documents and music across laptop, desktop and external drive. Windows only, which will be a problem for some (especially on this forum!), though of course a Windows machine can be used to sync to a file share hosted by another OS. Free for moderate use. Small fee for unlimited "pro" version. One of the few such programs I've ever paid for. Regularly updated with new functionality. I agree with others here that having a single approach for different kinds of data is probably not the right answer. For me, photos, documents and music are my three "buckets" of content, which I sync with different jobs and different frequency. OS and program settings are the other thing I backup manually, typically only when upgrading / migrating machines...