Shell script to get my public key from a url and append to authorized_keys to grant access

get_my_access.sh

#! /bin/bash
if [ ! -d $HOME/.ssh ]; then
        `mkdir $HOME/.ssh`
        `touch $HOME/.ssh/authorized_keys`
        `chmod 0600 $HOME/.ssh/authorized_keys`
else
	if [ ! -d $HOME/.ssh/authorized_keys ]; then
        	echo "Creating authorized_keys file"
                `touch $HOME/.ssh/authorized_keys`
                `chmod 0600 $HOME/.ssh/authorized_keys`
	fi
fi

#get public key from a public url, mine is at dropbox
PATH_TO_KEY="http://dl.dropbox.com/u/628209/manik.pub"
echo `wget $PATH_TO_KEY`

#todo - handle failure to get key

key=`echo $PATH_TO_KEY | sed 's_.*/__' `
`cat $key >> $HOME/.ssh/authorized_keys`
`rm $key`