Inherit/Extend CSS properties onto another element

Question

What's the most efficient way in jQuery to extend/inherit CSS properties from one element to another?

Desired effect

$('#blah').extendCSSTo('#me') // Is there a plugin or a good way to do this?
$('#me').css({ background: 'blue' });

#me will now have all the CSS of #blah and also background

CSS:

#blah {
    padding: 5px;
    width: 200px;
    height: 20px;
    border: 1px solid #333;
    font-family: "Verdana";
}

#me {
    position: absolute;
    left: 5px;
    top: 5px;
}

<div id="blah"></div>
<div id="me">test</div>

Edit: This will be used in a plugin so using classes and simply doing .addClass is not an option

I'm looking for the same effect as setting default value for plugin options, but instead for CSS:

$.extend([css object], [#blah css object], [#me css object])

Answer 1

$('#me').addClass('class');

This works, not sure if you can use the css relative to an ID though.