What I don't like about Dropbox is that it downloads every file from a common folder (shared with other people from my group) to my local computer, whether I'm

What I don't like about Dropbox is that it downloads every file from a common folder (shared with other people from my group) to my local computer, whether I'm interested in it, or not. It should just give me access to it, in the cloud, not just download everything behind my back and using up many, many megabytes, on my rather limited diskspace. (Diskspace is always limited, no matter how large disks get.)