Depending upon the systems and the files involved, you could try just mailing them between two users, or even scp'ing them (if unix, windows also has a winscp program one can download).

Failing that, you could write a client/server script that opens up a socket. Then read bytes from the file in question on the server and write them out the socket. On the client side, read from the socket and write to the new file. Primitive but effective.