We also use shared folders on our network but are moving our students and staff to google apps. There will no longer be a reason to have servers to host documents. All documents will be saved on google servers. Google Apps for Education is free and currently each user has in the region of 7 Gb of space. Check it out http://www.google.com/a/help/intl/en/edu/index.html . I know this is not the answer to your original question but it is an alternative.

It depends on the app. Some apps like GoodReader can read from some network drives. It also depends on the protocol, WebDAV might be supported but SMB might not.

But outside of specific apps, no.

Except that Google Apps is not writeable from the iPad :(

Google Docs should be editable soon as I was told by the folks at bytesquared.

Quote:

Google have a bug in their Api whereby it cannot open files created with the new editors. They are aiming to fix this soon. As soon as they do Office2 HD will start working. Kind regards, Simon Bates Byte Squared Support

Their app Office2 HD is great to access files stored in the cloud or on local servers.

OS 4 should have the ability to connect to network shares I hope. http://www.apple.com/iphone/business/preview-iphone-os/

Try NetPortalLite or NetPortal

Filebrowser , avsilable on the appstore will connect to smb servers