I have used Dropbox for some time as a way of sharing files between my desktop, laptop, and Android phone, and originally heard about it as part of a project I was working on. Here is an article that tells why it is valuable as a project management tool. You could do the same thing with Google Docs and similar tools.
http://pogue.blogs.nytimes.com/2011/10/20/dropbox-will-simplify-your-life/