Graduated senior year of college just last year. Right around graduation, I was going through all my old internal accounts when I found the internal housing portal for student dorms. I don't remember why I went into it, but I found a section where you filled out questionnaires before freshman year and could send people messages to try and find compatible roommates.

I had one message in my inbox, dated from before freshman year. I'd never answered or even read it. It was from one of my best friends and current roommate of three years, who I hadn't met until midway through freshman year of college. Apparently he had messaged me before freshman year and suggested living together, but I never saw the message. Then, of all people on campus to become friends with and eventually live with, it wound up him after all.

Tl;dr random guy messaged me suggesting we room together in freshman year of college. I don't discover the message until senior year when we'd been living together and best friends for three years already.