You can edit and save Word and Excel files and view ppt and pdf files and sync them with your iPhone using Documents to Go app in the iTunes store for 10 dollars http://itunes.apple.com/il/app/id317117961?mt=8
I've been using that for quite a time, and it's worth it
One other option is to run one of the VNC or Remote Desktop apps (about a dozen different ones in the App store) on your iPhone, and remote view your PC/Mac to see and edit the files.