Michael Ludwig wrote:
> Sprites are useful for collections of related of the same size and
> purpose.

You don't have to restrict them to images of the same size.  You can use
a sprited image to replace any fixed size image, and any background
image that repeats in one direction or the other (but not both).  One
caveat about that though is that background images don't print in most
(maybe all) current browsers.

In experiments with sprites and changes to some JS, we've managed to
reduce render times on our websites by nearly half, and reduced the
number of elements retrieved from the page to about a quarter of what
they used to be in some cases.

Adam