Spawn Illuminati is an iPhone version, with lots of extra features, of the old unix screen saver swarm. It's a great little fun toy with no real function -- other than to look at the pretty lights. I guess you could justify it as a background image generator -- but that would be a stretch.
The interface is rather odd with this application. You swipe you finger in a particular direction to change the size of the lines, speed, etc. There's a quick explanation of the controls shown when the app loads. In addition, the lines will follow your finger as you drag.
Here's a Youtube video (in usual YouTube quality, yuck) that shows you what the app looks like. The actual app is higher resolution, more defined, and much smoother.
I must admit that I was ready to give this app a much higher rating but the value seems less than it was. The developer changed the price from $0.99 to $1.99 while I was reviewing it. Obviously developers are free to set their prices at what they want, it's up to them. This is a well developed app, fun to play with, but you may grow bored with it quickly. Let's see what the developer adds in the future.