DropBox is a great time saver but it’s very limited in storage space. There seems to be no real other free alternative services (all online storage services don’t do automatic synchronisation and are not seamlessly integrated with the OS explorer). So why not look at opensource solutions ? There seems to be any ready-made one so you have to build it yourself by assembling several systems. fak3r has been experimenting with this; you can read his step by step instructions here though I didn’t test them myself as I don’t have a Linux but a Windows system. Any suggestion for Windows welcome or I will have to setup Linux one day Read more: Ask Superuser
Instructions: Build DropBox
Instructions: Build DropBox