I did 23andme by ordering two tests: one for me and one for my dad. I waited until I had my results back to send my dad his test, in case something came up that would blow his 80 year old mind.
We show up as 99.9% European, which surprised me because both sides of my family had ancestors who arrived in Virginia in the 17th century, and were slaveholders. My paternal grandmother's family arrived in rural New England during the colonial era too, so I expected some Indian or Sub-Saharan African genes.
Based on some of the names way back in my family, their involvement in the Crusades, and their history of alternating between piracy and the British Navy I also would have expected some North African or middle eastern ancestry. That shows up as the .1%, so small it could just be anomalous.
Things I found out:
1) My parents aren't second cousins once removed, as one family legend had it. In fact for having ancestry all over the same three or four counties over a period of centuries, they're totally unrelated;
2) My dad is part Italian, which we did not know about, as close as a great-grandparent;
3) My mother has a weird strand of something that keeps changing from Finnish to Eastern European to Ashkenazi;
4) My dad is 100% Euro, and a lot more Neanderthal than my mom (I'm 2.4%), but he has African American 3rd cousins in Mississippi;
5) My dad, through his father, has the "Niall of the Nine Hostages" marker for very old Irish ancestry;
6) both parents' families are much more continental Euro than we'd always thought prior to my sister doing a huge decade-long genealogy project, but the results fit my sister's data. My grandparents all thought they were Scottish. They aren't.
7) it looks like I'm going to die of esophageal or stomach cancer. Unlike my dad, I don't have the centenarian gene - he probably blew his by smoking for 50 years.
It was interesting. I'd do it again.