I was 17, skipped the last days of school and sold a forum-/chat-/etc. software to the largest german TV channel. The software didn't actually exist at that tim

I was 17, skipped the last days of school and sold a forum-/chat-/etc. software to the largest german TV channel. The software didn't actually exist at that time, I had to make do with a prototype built in powerpoint. We got about 20k€ iirc, and later learnt that we should have probably added a zero to that. Took us quite a while to build it and became a bit much for me to manage that project, but we got it done mostly intact. The whole thing was quite a mess of php spaghetti-code, though. Still had a lot to learn.