Feature: Custom target field for links (for iFrame targeting)

Hmm. Someone helped me out a little with what would go into a plugin that does this, though honestly I have no idea how to code plugins. Could someone take a look at this? Also, I would be willing to pay for a plugin with this functionality.

function arlieth_link_target( $link ) {
copy the form from the previous box, but change the target element
from a radio to a input text
}
function replace_link_box($page, $context, $link) {
if ( $page != ‘link’ || $context != ‘normal’ ) return;
remove_meta_box( ‘linkadvanceddiv’, ‘link’, ‘normal’);
add_meta_box(‘linkadvanceddiv’, __(‘Advanced’), ‘arlieth_link_target’,
‘link’, ‘normal’, ‘core’); // <– notice that here I put the name of
the new function instead of the old one
}
add_action(‘do_meta_boxes’, ‘replace_link_box’);