Menu Icons Module

DESCRIPTION:

This module allows you to upload an image in the menu-item's configuration form.
The uploaded image is added as an background image to the menu item.

USAGE:

After installing the module you can configure its global settings by navigating
to: admin/config/user-interface/menu_icons. Uploading an image for a menu-item
can be done at the menu items settings form (e.g.:
admin/structure/menu/item/1/edit).

The text of the menu item can be hidden by the adding the following CSS code to
your theme's stylesheet:

.menu_icon {
display: block;
overflow: hidden;
padding-left: 100%;
}

DRUSH:

nb: if you clear cache with drush without a site explicitly configured,
the CSS generated by menu icons will be incorrect. This is due to a
limitation of drush, in that it doesn't know the site's URL if you don't
tell it. To pass the site's URL, use the -l flag to drush, or better
yet, permanently configure drushrc.php. For more information, see:
http://drupal.org/node/1520414 and http://drupal.org/node/743368