SquareOne notification style for Growl
v1.3 and newer. At minimum requires Safari 5.1 and Mac OS 10.6. Plays best on Lion, OS 10.7, and newer.
SquareOne is small, variable width and only roughly 26 pixels high. The notification pops up with a rough, bouncy, magnetic rail animation - a train with no breaks. Designed for the top-right corner of the screen.
The icon in the preview is by Umar Irshad
from his Build icons