For the longest time, I've come up with app ideas that would be great as simple utilities confined to the menu bar as a menu extra, but I never actually got around to learning what that entailed.
Well, it's actually pretty simple, as various tutorials make clear. So, to keep me from making excuses next time, I've created a simple template app and put it up on GitHub.
If you have any questions or find a bug (geez, I hope not), write up an issue on Github!