Where do you come from?

I have just discovered (thanks to my new friend massimo) an exciting and massive DNA-testing of people sponsored by the National Geographic: The Genographic Project. In practice, you subscribe, get e-mailed at your place a DNA-testing kit, then spit on it, send it back and they'll let you know where your ancestors came from. Of course you know who your father was, and your grandfathers and so on... But then? This way, if you're italian you'll discover that may be you're one of the few survivors of the pre-indo-europaean populations, or may be a late-comer born out of a barbaric rape following the Roman Empire fall. Who knows? May be this will be my Xmas present to myself. And may be I'll give one too, so that I'll discover when the common ancestor of Marie and mine lived. You never know, we may be cousins (yes, at the 7569th level may be).