Add your ssh key to a new remote version

ssh-exchange.sh

#!/bin/sh

KEY="$HOME/.ssh/id_rsa.pub"

U=$2

echo $U

if [ -z "$U" ] ;then
	U=deploy
fi

if [ ! -f $KEY ];then
    echo "private key not found at $KEY"
    echo "* please create it with "ssh-keygen -t rsa" *"
    echo "* to login to the remote host without a password, don't give the key you create with ssh-keygen a password! *"
    exit
fi

if [ -z $1 ];then
    echo "Please specify user@host.tld as the first switch to this script"
    exit
fi

echo "Putting your key on $1 for user $U... "

KEYCODE=`cat $KEY`
ssh -q $1 "useradd -m $U ; mkdir ~$U/.ssh 2>/dev/null; chmod 700 ~$U/.ssh; echo "$KEYCODE" >> ~$U/.ssh/authorized_keys; chmod 644 ~$U/.ssh/authorized_keys ; chown -R $U ~$U/.ssh"

echo "done!"

Based on http://hints.macworld.com/article.php?story=2007091814022049