My parents died before I became curious about these kinds of things, and most of my background and heritage is in Europe (UK/Ireland/Germany) so I was delighted when I discovered this!
I am mainly interested in finding out my heritage, and not finding lost family members, though that is what many people do.
I used the Swedish equivalent of this site, and just want to find out my ethnic mix. There are different tests you can order (for example a maternal line or paternal line) but I just ordered the basic one. It arrived today and now I have to take a swab from my cheek and send it back.
Will keep you posted!