Drop shadow with CSS for all web browsers - Robert's talk
http://robertnyman.com/2010/03/16/drop-shadow-with-css-for-all-web-browsers/

Como aplicar sombras con CSS en TODOS los navegadores web.

"One of the most common CSS effects is using shadows in various ways. Before, we needed to resort to images, but now we can offer this to all major web browser with CSS!"