It's Soothing Until the Moment It's Terrifying

I forget who I got this link from (probably Jay Lake), but there's an animation by Kevin Drum right here that shows (along with his accompanying article) exactly why High Frequency Trading is a bad idea.

If you don't know what HFT is, it's automated, computerized stock sales by software robots -- millions of times a second, often to make fractions of a penny. Most of us could probably figure out a dozen reasons why that wouldn't be a good idea...and that's why we're not Masters of the Universe.