Ok, i prepared a Google Drive public account (15Gb included). It's the only way i know to do this, 'cause Dropbox has stopped public folders since some time. I set the folder public and everyone can download and upload files over there. I guess that if you wanna upload files you should be logged in with your gmail account, but i'm not 100% sure about it. We can do some tests. Here's the link:
Let me know
Cool, I will try to upload something soon. Not sure if I will be able to before the weekend.