Mac\Windows question

Folks-

I'm about to try something and wanted to see any of you has any pointers...

As part of my video editing station, I have a windows box setup to process my green
screen editing (the vendor, serious magic, only supports windows).  All of the output from
this machine goes over to my dual g4 running Final Cut Pro.

I have a 250 gig Lacie external hooked into a firewire port on the G4 for scratch file and
editing.

Both machines are on the network.  The problem I have is that when I transfer a file from
the windows box to the G4, the network suffers.  What I was thinking of doing was
connecting the G4 and the windows box with a firewire cable and then sharing the Lacie
drive on the G4 so that the windows box could access it.

My question is: can you create a peer to peer from windows to mac on a firewire
connection?  If so, do any of you know what steps to take?

Thanks!