Say you have a paragraph with the CSS of color: red;. If you would want to add a border in the same color you would just have to type border: 1px solid;. The border-color inherits from the paragraphs color property.

How about using your element’s color value for other things than border-colors? A neat CSS keyword I didn’t know about makes this possible: currentcolor. Treat it as any other color keyword (like red, blue, green etc.) and wherever it’s used, the color of the color is used.

p {
   color: red;
}

p span{
   background: currentcolor;
}

Firefox, Safari, Chrome and Opera supports the keyword but alas, not IE9 yet.