If, for some reason, you’re having trouble networking two BeOS machines, you can still transfer files between them over a serial connection (via null-modem cable). Download a copy of Jerome Fillon’s SerialTransfer. A precompiled binary is included, but so is the source code, so you can modify or re-build it if necessary. Place a copy of the binary on both machines.
Zip up the files you want to transfer, then, on the receiving machine open a Terminal and type :

Transfert READ serial1

(of course this could also be be serial2).
On the sending machine, open a Terminal and type :

Transfert WRITE serial1 MyPathAndFileName

There should now be a file in the /boot/home directory with the filename you specified.