"How do I make my own Dropbox without using Dropbox" is a question we get a lot on ServerFault.
And judging by the Dropbox Alternatives question, the answer is pretty clear.
iFolder.
Yes, that Novell thingy.
I've used the commercial version, but the open-source version does most of what the paid one does. I suspect the end-to-end encryption option is not included, possibly due to licensing concerns. But the whole, "I have this one directory on multiple machines that exists on all of 'em, and files just go to all of them and I don't have to think about it," thing is totally iFolder.
The best part is that it has native clients for both Windows and Mac, so no futzing around with Cygwin or other Gnu compatibility layers.
Of course WebDav can be SSL encrypted and is old as dirt. Plus Windows, Mac, Linux, BSD, etc can all mount it natively. But I suppose a proprietary or YAOSS (Yet Another Open Source Solution) will do.
This provides something that webdav can't, and that's access with full-blown file semantics, as well as offline access. Also, it does have the ability to do sub-file updates, so only the changed chunks of a 1GB PowerPoint will get transmitted.
For just exchanging files, a WebDAV share will work just fine so long as you have connectivity. Also, easier to set up.
WebDav is 'just' another file server method. The data is really just in that one place, so if it dies all the data is gone. Also if your connection is bad or down, you don't have access.
iFolder is data/file replication. So if one system dies, you still have copies on the other instances. Also works really well in low speed environments, and even without a connection you still have the data with you (assuming your local system hasn't become unusable.
At a backup seminar recently, Dropbox had been mentioned along with the 'lack' of being able to build your own. I described iFolder to the crowd and I say many taking notes, and after one guy ran me down to make sure he had the details correct as he was really interested in deploying it for some remote teams.
Isn't iFolder a lot of work to get installed? I seem to remember that the packages were only available for SUSE, and almost nobody runs that. I specifically remember a lack of Debian/Ubuntu packaging.
IFolder works only with SUSE, but this seems to be only option fot self-hosted Dropbox alternative.
Yes, iFolder is a TON of work to get installed. I've been battling with it for hours now, and am about to give up. Most of the instructions appear very outdated and the repository paths have changed. I'm finding it easier to install on Ubuntu!