Your Genetic Journey
Apart from the rampant pornography (sorry, couldn't choose just one link), the next best thing the Internet should be good for is the convenience of collective learning, compiling data from a wide variety of sources with efficiency and speed.

Perhaps the most fascinating example of that yet, though not without controversy, is The Genographic Project, A National Geographic endeavor profiled in the NYTimes: (via The Loom)

The National Geographic's program, if it succeeds, will create a collection of blood samples 100 times larger than the Human Genome Diversity Project did. Dr. Spencer Wells, a population geneticist at the society who is leading the program, said he hoped to head off charges of exploitation by offering money to the tribes for education and cultural preservation.

Many indigenous peoples believe their ancestors have always lived in their home territory, a credo that will not be supported by genetic analysis of their blood samples. Dr. Wells said that he would "tell people up front" that some of the results may contradict what they believe. "The idea that we have all come on a journey from a common origin is intriguing to people," he said.

The project will ultimately give you the chance to trace your DNA across tens of thousands of years of human migration. The interactive map already available astonishes in breadth and ambition. Select a time period, then an area where significant archaelogical findings yielded a particular genetic development, then follow the lines tracing that genetic marker across the globe, many of them all the way to the present day.

Best of all? You can help with the building of the genetic atlas by providing your own DNA (anonymously) to discover your genetic lineage perhaps as far back as 60,000 years. If the participation kit didn't cost $100, I would probably do it.