I got a Facebook message a couple years back from a guy in Sweden who was way too excited to tell me he was a distant relative. I was really skeptical, because while I'm 1/8 Swedish, I had only ever heard of it coming from my dad's side, and this guy was talking about people from my mom's side. Decided to respond anyway. Turns out he's just a dude in a pub band who really likes genealogy. Sent me this huge tale that ended with the fact that I'm related to Cleopatra, but I think everyone is in some way. Then he started to get into stuff that was more relevant to my family.
It ended up we were very distant, like only due to marriage a couple generations back, so nothing that would show up on a blood test I believe. Gave another story about how another distant relative (this one blood related) was in the Revolutionary War. Then he said he was coming to visit some 2nd and 3rd cousins of mine in Michigan in a few months. It still seemed really weird, but I never heard anything about a mass murder and he's still posting on Facebook so I figure it must be legit.
I'd like to get into it sometime, but it seems pretty arduous and can get pretty costly if you wanna find a lot of info, although the DNA test is only like $99 so I guess that's not terrible.