Use trickle! (apt-get install trickle for debian/ubuntu users)
instead of
ssh you@example.comyou use
trickle -u 123 -d 456 ssh you@example.com
where u is the upload limit in kbytes/s and d is the download limit in kbytes/s.
Very handy. I use it to rate limit file synchronization with unison. I have a ssh.sh script with
#!/bin/shin it, and sshcmd=/path/to/ssh.sh in my unison profile.
trickle -u 20 -d 40 ssh "$@"
Good luck!