I’m in no way affiliated with Dropbox, but it’s such a great idea and tool for writers!
Basically, you join Dropbox, which becomes something of a location on your computer, save files to it (including files for collaboration or files too large to easily email), and then access them anywhere over the Internet. You literally follow the same saving procedure as usual, but indicate Dropbox as a starting point rather than Desktop, Downloads, etc. To access your files from your regular computer, you simply click the Dropbox icon, which–surprise, surprise–is an open box.
An important writer’s rule for me is to have a single working manuscript. I might save previous drafts if I’m going in a new direction, but I have a single working manuscript. [Consider naming it conveniently, “Working . . .”] Dropbox lets me update that single document from my desktop or my husband’s laptop, and, when it is saved, it syncs with the other places whenever they are next connected to the Internet.
It is free of charge for limited storage and you can share entire files or single documents with others! Of course, google docs will let you do that too (if I remember correctly), but Dropbox has really pleased me as a way to backup data and have easy, shareable access. Pictures and videos can be easily shared too, for anyone wanting to share with friends, parents, or grandparents.