Pen-small

High performance scp

To copy a large file (1GB or more) over from one server to another use:

scp -c arcfour target username@server:/destination

this significant increases the transfer speed by at least 30%

For a little explanation:

http://web.archive.org/web/20120514155629/http://www.psc.edu/networking/projects/hpn-ssh/theory.php

This option is compiled to most of the ported scp.