circumventing a powermac/NAT router

[Luis Morales]

Greetings,

I have been advised here previously to conceal my home network behind an old 
powermac which would be used as a NAT router.  Now I have to consider 
whether this is worth the expense because if someone is dead intent on 
pilfering your research papers and they know where you submit them, wouldn't 
they be able to defeat your secure network by stealing your files on the 
receiving end?

Perhaps a concrete example will illustrate:

i have a mac mni behind a G4, i send a research paper to WebCT and Turnitin--
that file will now be purloined by the heathen subject, the pawn of Baalzebub 
itself.

Could this happen?

Regards,

-LM
-Luis Morales