I've always liked Dropbox, except for one thing: I don't trust them with my data. Also, it seems wrong to pay $ 10,00 for 50 GB of storage when you have your own server with much more storage and available on a fast network. With all these uncertainty, it is good to seek out Dropbox alternatives that are more trustworthy.

Well, finally there is a solution. It's called SparkleShare and it's completely open source and uses Git as a backend. Today they released a very early alpha version and I tried it out immediately. After having some trouble with the interface (you need to insert <username>/<reponame> in the folder input box if you use Github), everything worked great. However, I don't advice anybody to use it in production. It's still in development and can contain serious bugs. I can't wait till it gets more mature and ready for production usage!