I found this image while browsing on brandsoftheworld.com and thought it to be a good example of a simple, visual logo that displayed gestalt principles.

First off, the colors of red and blue are both engaging, and the red in the center is a very eye catching device because your eye immediately sees "bank" before going down to the slogan.

I thought the curved lines around the words were a good touch, because it shows symmetry and closure. I like how the lines haev a varying thickness for a dimensional touch. The curved slogan at the bottom follows the lines closely, so the logo feels very "finished" to me.

I like how the words "Atlantic" and "Southern" are in two different fonts--a sans serif and a serif. Between that the color change, it is readable and clear even though the words are right next to each other. The grey seems to dominate just enough over the blue, probably because that's what fills the bottom half of the logo.