The Internet has revolutionized genealogy, however most people can only trace their family tree back to the beginning of the 19th century.
The price of genetic tests is dropping exponentially and it is now possible to test markers on Y Chromosome (male lineage) and Mitochondrial (female lineage) DNA to show where you came from over a 100,000 year timescale for $200.
What is so special about genetic genealogy is that it almost entirely dispels racist ideology. Although first identifiable humans appeared 2M years ago and spread throughout the world, all of us are descended from around 20,000 people who left Africa around 100,000 years ago. Although the Chinese government may insist that different races evolved from earlier hominids we are in fact all Africans.
While in the UK I met with the maker of The Journey of Man a documentary which tracks the ultimate genealogical goal, the trail of humans as they migrated from Africa. A new series of documentaries is being planned which will undertake the most ambitious genealogical study in history.