One day I got an unexpected email from someone asking permission to use a piece of code on github I forgot I wrote almost 10 years ago without a license clause. I was very surprised and confused because I forgot I wrote that code, and I was not involving coding for quite some years and my github profile was blank without any contact information. I asked. It happened the guy simply made a search and found a post on a forum with my nickname, and email address - newly created recently. At that moment, it clicked and I felt some unusual arrangment. I quickly added an open source license, and the guy, CTO of a decent company, offered to make a donate. That made me a day.