This hit me years ago. I had 5 or 6 clients who were all raving about how great and free dropbox was. Each shared files with me, but it put me over my own limit. Each of them were only sharing a few hundred meg, but it put me well over the 1 (or 2?) gig limit, and I had to pay to continue using it to get their files (which was free for them). Left a bad taste in my mouth.