I'm a huge fan of Dropbox. I have it on all of my home computers and linked to my network drive at school. I have access to my files from any computer and from my Palm Pre+. I can view, edit, and upload files from anywhere. I also use it to share files with the other instructor for the paramedic program I teach at (very large files).
I just posted about AirDropper (and earlier about DROPitTOme). Both are apps that work with Dropbox.
Dropbox's site also has a listing of apps that work with Dropbox.This is not unusual. Many web services are teaming up with other web apps to work together to provide more functionality to their service.
Some of the apps for Dropbox include office productivity apps, file readers, editors, scanners and much more. Many are smartphone apps, others are web apps. Check them out and see what's available to help you be more productive.