We're primarily a Novell shop, but we have user home directories and
departmental shared directories on Windows 2003 shares.

Novell has a product called Netstorage:

that lets users access all of their network drives via a web browser.
Users can upload, download, and otherwise manage the files on their
various network drives using just a browser.

I know we could put the shared drives on a Netware or Linux NCP/NSS
volume and use Novell Netstorage, but our luck with that has been hit or
miss. Backups on our Windows servers happen about twice as fast as
Netware, and once in a while the backup agent will abend the server.
Plus, getting stable antivirus software for a Netware fileserver seems
next to impossible. We've looked at various options on linux too.
Quotas, shadow copy client restores, antivirus, backups, etc., just seem
to work much easier on Windows.

Is there anything like Netstorage that available for Windows? There are
a couple Flash demos on the Novell site to give you an idea of how it works.