It is a free service that works with Dropbox.
Registering at the site is simple. You receive a unique upload address with password protection. I create a very simple password that students memorize. I also give them the link directly to my account.
All they need to do is provide the password, browse for their file, and upload. My elementary students can do this in less than a minute!
I can see the files as they appear in my file. I usually open the folder and project it so students can double-check that I received it. I can leave the files in my DROPitTOme folder or transfer them to others. The days of trying to attach large files to emails or transfer via flash drives is over!