6 Scan important personal documents—your passport, driver’s license, marriage certificate, and so on—and store the scans in Dropbox; that way, you can get to them anytime you need to provide a copy.
Archive the original installation files of your apps so that you can install (or reinstall) them as necessary
Download PDF copies of the user manuals for products you own
Just remember to be careful if storing personal files in dropbox....know how secure it is or increase security...I love dropbox but use it for files that are not confidential and do not have my personal information...
I love the idea of sharing photos through Dropbox instead of in e-mail. They upload quickly and you don't lose the quality of the photo like you might when you share on picasa or another photo share site.