I recently (as in about two hours ago) finished reading Watchmen by Alan Moore and Dave Gibbons, and this idea struck me. Rorschach is one of the main characters, and if you know what he looks like, he should be pretty prominent in the image. Hopefully he stands out even if you don't.
I drew this entirely with the pen tool in Photoshop. It took about 20 minutes.
As a wallpaper, it's kinda funky. It makes icons a bit difficult to see, because of all black and white mixing together. Heck, even as a regular image it's kinda funky. It messes with my eyes.
This might've been more effective had I done it with actual inkblots, but it's almost five in the morning, and I don't have the necessary materials on hand, and I almost definitely would not purchase them even it were a more reasonable time.