A DNA test and 3 months to trawl through your family history.
Big warning to cancel before renewal, as that costs $129/3 months. You'll probably have gone down all the branches by then anyway.
Not sure if you can simply cancel straight away to keep the 3 months, maybe someone out there can let us know.
Sure private company, in a world where dataleaks are becoming common and biometrics are one of the few more secure methods we have left, please take a copy of my DNA.