Pricing is as follows:
Installation is easy and once it’s installed, all you do is drag your files into the Dropbox folder. Once in your folder you can view, open, and change files from any computer or device with Dropbox installed. Add a file on your office computer and it will show up on your iPhone and vice versa. Information is encrypted via an SSL tunnel in transit, and any files on the Dropbox servers are encrypted using AES-256. Files are also viewable by logging into your Dropbox account on the web, using your username (email address) and password.
Dropbox offers some backup features as well, including undelete and previous file versions.