I know its probably something you just do manually, but is there a good trick to doing this sort of effect? I want to take an image I traced in Illustrator CS2, and have the back side of it "pixelize" like this horse. Do I just have to go in and start creating little squares?
You can do this in Photoshop, and then move the paths back into Illustrator.
First place you logo on a layer in photoshop. Then add a layer mask, and drag with gradient over the logo to make the tail end fade out. Change the image mode to grayscale then
filter >> pixelate >> color halftone
filter >> pixelate >> mosaic
image >> adjustment >> curves (maek an s-curve to eliminate midtones eg: input 31 output 16, input 64 output 79)
Slect teh solid black square, then in path palette flyout menu choose >> make a work path.