This application is free.  It is amazing.  And everyone should be using it.  Seriously.  If you have an iPhone, you need to get this app.  If you don't use Dropbox on your Mac yet, go to www.getdropbox.com and start using it.  Seriously.  So nice.  You have all your important files right with you.  You can download the important ones to the iPhone.  

So in all seriousness, if you have an iPhone, get this app.