Multi-select drop down is light-weight, customizable, cross plataform depends on grails jquery plugin.
Provides a tag library having tags for including resources and dealing with HTML select boxes specially with multiple attribute set to boolean true. Using Multi-select drop down is similar to grails select tag. This tag pops out all the selected options from the select box, leaving only the deselected items. The selected options are displayed as list below the html select box with deselect button along with each option. The items being selected from the select box are added to the selected items list and removed from the select box. Similarly deselecting an item from the selected items list removes it from selected items list and adds it back to the select box. This separation of the selected and deselected items makes UI more meaningful specially when no of items are huge. The css for displaying selected items are customizable.