Now this is artificial intelligence at work.

The program monitors people's habits for a couple of weeks, quietly making decisions based on what it has "learned." A couple of weeks after installation, for example, the program might determine that a worker rarely responds to certain bulk e-mail from the human resources department, and so those e-mails would receive low-priority placement. In theory, the longer the software is in use, the more precise it becomes at prioritizing.
http://news.com.com/2100-1023-946952.html

One of the ironies of computing is that, even though it is supposed to be a time
and labor saving device, computers require time and labor invested if you want
to be productive. E-mail, a great time saving invention, occupies too much
of our time. Writing and customizing a filter would solve that problem, but it
takes time to customize the filter. So now, there are self-customizing filters
that will adapt to your habits.