Aged posts get smaller

Hi,
I am looking for a theme with a special functionality. Here it goes.
On newspaper sites stories start out on top of the page with a large image. As the day goes the story moves down the pages and becomes smaller. New and fresher stories take the top. I don’t know what this functionality is called. any clue?

Like this:
[——— THE NEWST STORY ———]
[—2 HOUR OLD—][—3 HOUR OLD—]
[–6 HOUR–][–8 HOUR–][–10 HOUR–]

Anybody know of a Blog theme with this functionality or just a theme with different size post. (then I can have somebody code the aging of the stories)

Thanks in advance