The simple file dropbox
Sometimes it's nice to be able to create a file dropbox that allows a number of people to hand in a file, perhaps a class assignment that's due, or to create a book in which everyone hands in a section. If you are looking for something that gives you a lot of control over the submission process and permits only you to access the submitted files, a Webform will work for you.
The webform is simply a survey device, and it allows one to upload a file as part of the survey. Therefore, you can create a simple dropbox by creating a webform with no text in the body, and then adding a "file" form element along with extra elements such as a name, feedback questions, etc.
How to set it up
Go to Add Content -> Webform, and enter a meaningful title with no text in the body (unless you need to inform someone to log in or log out). Click "Save" at the very bottom of the form.
Next, click the "webform" tab at the top of the newly created webform. This will put you on the Form Components tab under the Webform tab. Select "File" from the dropdown box and click "Add," not "Save." You will then be presented with a list of options for file uploads, with the most important options being the allowed file types and maximum size.
After this, use the same procedure to add text fields (for entering a name), and feedback forms like textareas, select options, and grids.
Once you are ready to collect your files, go to Results -> Table. The files will be listed for each submission, and you can click to download them.
In addition to these core controls, a few controls to be aware of are the email notification settings under webform -> E-mail, and access control settings under webform -> Form Settings. E-mail notifications inform you of new submissions as they are sent. With form control settings, you can control how many times a user may submit an entry, and what level of user may make an entry on a form. For example, a teacher could have students log in via Facebook, set the webform to accept authenticated users only, and delete any entry that doesn't correspond to a known student.