I had a co-incidence that wasn't internet-related but seemed like an OK co-incidence to me. About 13 years ago a good buddy called me and said he had someone who wanted to meet me, being skeptical I was all "yeah, sure
" but he carried on so I realized he wasn't kidding. He'd been dating a woman for a few months and was driving past my Dad's commercial property with her and her sister when he pointed out the building and noted he knew the owner. Turns out they did too as their Mom dated my Dad around 1991! Back then I had helped them move when they were leaving the Mom's alcoholic abusive ex (he was not the father of the girls). I was about 21 at the time and back then I had not met the older sister that my pal was dating as she was living somewhere else, but her younger sister I had met and she was about 16 at the time. Turned out she had a bit of a shine on for me way back then so when the 3 of them realized the connection they conspired for us to meet. We wound up going out for a while after that but split after a few months. My Dad was relieved at the break up as he didn't want to have to cross paths with her crazy mother again
.
Bumped into her a year or two ago and chatted for a while, it turned out she was my step-nephews boss at her workplace..... the degrees of connection with her never seem to get very far away.