The night I met my fiancee, we were both working in the same building. It was just a chance meeting, we made smalltalk for a bit, and then went back to work. About 10 minutes after she took the elevator to the next floor, I went to the other end of the building, and took the other elevator up a floor, hoping to "casually" catch her to chat some more. When the doors opened, she was right there. That'll be five years ago in two weeks
She actually approached me. She'd overheard me talking with another coworker about Star Trek, so she asked me about it. When I caught her after, I offered to stream a couple of TNG episodes and watch them with her, and I gave her my phone number. We got really lucky with compatibility right off the bat. In that same conversation, we found out we have the same favorite video game