Ultimate Tic-Tac-Toe is a finished project. It is near tic-tac-toe in rules and gameplay, except played on a 4x4 grid and you need to get 4 in a row to win.
You play against a friend (or yourself) and there is optional background music.
This is the first project I've ever undertaken, and is also the first 'real' program I've done, except for "hello world" type things. I programed it using c++ and SDL, so it should be completely cross-platform. I was only able to provide a Windows binary, but I was able to easily and quickly build it on Linux. Instructions are included in the README file.
These details are provided for information only. No information here is legal advice and should not be used as such.