I wrote a program to implement a half-QWERTY keyboard on a full-QWERTY keyboard (holding the space bar horizontally flips the keyboard layout) while I was recovering from a serious bike accident and didn’t have any use of my left hand for several weeks. It was my first time writing a Mac app and my first/last in ObjC. I built it so I could work more efficiently while I was injured, and because I needed to work.
I didn’t release it to the public because:
1. It very probably would violate patent law, and I don’t want to find out.
2. It was extremely crashy, probably because I was more concerned about making something kinda work than learning memory management. (The only change I made restarted it when it crashed.)