It can be done, but do you have a firewire cable? It would be easier. Boot one computer while holding the "T" key. Connect them with the firewire cable. The one in "Target mode" should appear as a firewire hard drive.
Edit: if you don't have a fireware cable, connect the two computers with the ethernet cable and manually give them IP addresses. FTP from one to the other. If you need more detail, let us know.