From the website:
Dropbox is a free service that lets you bring all your photos, docs, and videos anywhere. This means that any file you save to your Dropbox will automatically save to all your computers, phones and even the Dropbox website.Dropbox works with Linux, Mac, Windows, and mobile devices. It’s changed my ways of working: I no longer need to send myself attachments or carry a flash drive to have access to my stuff from a classroom or office computer. The stuff is just there.
If you’d like to try Dropbox, here is a referral link that will give you and me each an extra 500 MB of free storage.