Highlight custom widgets in the admin area?

All widgets in the admin area get an id in the style widget-[global_counter]_[widget_key]-[widget_id], like widget-59_monkeyman_widget_shortcut-5 (installed widget) or widget-11_monkeyman_widget_shortcut-__i__ (an uninstalled widget in the list).

If your widget key contains something unique for all your widgets (like your company name), you can use this and add a substring attribute CSS selector (which works in most browsers). In my case div.widget[id*=_monkeyman_] does the trick, so I add a little CSS snippet in the widgets.php admin page header:

add_action('admin_print_styles-widgets.php', 'monkeyman_widgets_style');
function monkeyman_widgets_style()
{
    echo <<<EOF
<style type="text/css">
div.widget[id*=_monkeyman_] .widget-title {
    color: #2191bf;
}
</style>
EOF;
}

This gives me the following result: