Thanks for the feedback.
Although I never got any answer to what I asked:
“… is it possible to retrieve a filelist and retrieve a hash key of a file/data block?”
“are there already a .Net class out there that could be useful?”
“Should I use webdav to transfer files?”
But I’m guessing the answer is “no”.
The storage solutions from Azure, S3 and Google all have that…I just wanted to know if ownCloud could be used as an alternative to those cloud storage solutions.
It’s obvious it’s not a good idea to use ownCloud’s synchronization functionality directly as a backup solution, and I didn’t ask about that.