Sorry for bringing this up.
I havent seen the movie Firewall ( yet.. i plan on it)
Im a electronic engineer.
A few things has to be possible with the iPod in order to make this work.
So at least in theory this DOES indeed work:
The scanner module is as far as i know from a fax right ?
A fax machine sends the data as sound tones through the phonelines. If the iPod is able to record the tones it wouldnt mind what those tones contain. And it would indeed not matter if its 10000 songs or 10000 accounts.
Once the iPod starts to record ( once tapped into the phoneoutput of the fax ) it would actually be possible to reverse it.
Once the initiated handshake from fax to fax has been established the playback could possibly be printed out on a reciving faxmachine.
Now.. If a scanner is actually able to pick up anything from a monitor i do not know. But i would think its somwhat possible. Not pretty but readable would be my guess.
It sounds like a case for the mythbusters really

but i do think its possible. At least plausible yet unlikely.