_complete_ssh_hosts ()
{
        COMPREPLY=()
        cur="${COMP_WORDS[COMP_CWORD]}"
        comp_ssh_hosts=`cat ~/.ssh/known_hosts | \
                        cut -f 1 -d ' ' | \
                        sed -e s/,.*//g | \
                        grep -v ^# | \
                        uniq | \
                        grep -v "\[" ;
                if [ -f ~/.ssh/config ]; then
                        cat ~/.ssh/config | \
                                grep "^Host " | \
                                awk '{print $2}'
                fi
                `
        COMPREPLY=( $(compgen -W "${comp_ssh_hosts}" -- $cur))
        return 0
}
complete -F _complete_ssh_hosts ssh

Thanks for the slick inclusion of .ssh/config. However, I had to make a quick tweak to 'awk' out the 3rd entry rather than the 2nd.

awk '{print $3}'

My .ssh/config uses this syntax, which may or may not be 'standard', but definitely works. My config syntax comes from ssh v. 1, so the current accepted syntax could be VASTLY different.

Host = solutions