Create Synchronicity, created in 2011, is an open source solution based on Visual Basic.
Like Sparkle share, the language pair (vb or C #) net. and open source project show that all the solutions are likely to be open source regardless of their technology.
The solution, however, is reserved for advanced users: the interface is not very intuitive despite a list of very interesting features: full or intermediate synchronisation, storage backup (can be scheduled, it is also the basis for the creation of this project "synchronisation backup"), comparing file size, etc.
The solution is particularly well documented (manual, FAQ ...). However, it does not currently have a versioning system.
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