Ick, no images in sigs, please. I've seen it on other Forums and it is just out of hand, distracting and annoying. If your sig is larger and more noticeable than your post, that's just plain wrong.
I was referring to images, larger font text in a sig or the length of the sig being longer than the post itself (see the post right above mine for an example ) but yes, perhaps I will go back to my standard size 1 black text sig again...