Dropbox for Business lets you limit your coworkers' access to shared files
 

Dropbox for Business is good for collaborating on files stored in the cloud, but it hasn't had fine-grained permission control -- not great if you have a sensitive project you'd rather not share with the folks in Accounts Receivable. You'll be glad...

http://www.engadget.com/2014/07/23/d...=rss_truncated