A few years ago I hired a landscaper who wouldn't return my calls or fix his shoddy work after screwing the job badly. If I wanted to warn others about this, I could use Sidewiki to leave a note about my experience. I'm sure he would disable it if he could, but the fact that he can't is the beauty of such a system. I'm not changing his content or using his server--I'm using a Google service.

In "The God Delusion" by Richard Dawkins, he makes the point that there are approximately a billion billion planets in the universe within the so-called "goldilocks zone", that is, capable of sustaining life because they probably have liquid water. So, even if the likelihood of DNA or RNA randomly forming was a billion-to-one, that would still mean that it has happened on a billion planets.