iPad as a USB drive?

In that situation, there is no way. There is no 'media store' capability built in the iPad, and Apps like DropBox and Flash Drive emulators all require a wifi connection to access the files. None will allow you to plug your iPhone into a computer and use it as a flash drive.

A search of the iPhone forums will explain why Apple do this.

AirSharing HD is proably the closest thing to a files system for the iPad. Read the App Store description carefully to see if it does what you need before investing in it.

Kevin Wolfe1 wrote:
AirSharing HD is proably the closest thing to a files system for the iPad. Read the App Store description carefully to see if it does what you need before investing in it.

Which won't work as the OP is not permitted to have wifi ...

I'm creates a local filespace on the iPad that allows storage and has an extensive set of readers.

Not sure what youwant to do with the files once you get them there but there are other options as well. You can file attach them to your email account and read the attachment on your ipad. I think you can even open it up if it is an office or iWork file and you have iWorks on your iPad (not sure if current version works for that yet but OS 4.0 will). Another option is if you have a Mobile Me account you can transfer the files there, download the free iDisk app. From there you can read the files (if supported)

Hope this helps,
Tom

Confirming: If the attachment in email is downloaded and supported by Pages you can read it and have the option to open it in Pages or Keynote, edit it and save it on your iPad or export it back to mail. You can do this without a connection.