tsBorder

tsBorder allows you to overlay a semi transparent border on block elements. You can choose your preferred border colour, opacity and thickness in pixels.

Example:

Adding a 10px black border with 0.3 (30%) opacity

    //black 10px border
        $('#box1 img').tsBorder({
                           thickness: 10,
                           color: '#000000',
                           opacity:0.3
                          });

See http://faffyman.github.io/tsBorder for more examples.