The National Geographic Society has running a project called the “Genographic Project” that is traces the geographic roots of our ancestors. By tracing DNA markers, it is believed that all living humans are descended from a group of about 2000 that lived in Africa about 60,000 years ago. The web site has an interactive timeline that lets you follow the various routes our ancestors took across the globe. They also have a pitch for you to submit your own DNS samples from a kit to contribute to the process.