I made and maintained a geo-based chat app for a friend/client (https://hihey.org https://hihey.org, though they took it offline for now I believe). I used Matr

I made and maintained a geo-based chat app for a friend/client (https://hihey.org https://hihey.org, though they took it offline for now I believe). I used Matrix as the basis for it and started putting that on my resumes after finding it fun to work with and experience. I got a couple of reach outs based on having that keyword on my profile alone on YC's job board and on LinkedIn that led to some paid consulting. Not as life changing as some of the other answers but I'm amazed when this sort of thing even happens