Here is another port of a BASIC game from Tim Hartnell's 1984 book "The Big Fat Book of Computer Games".
This is a GUI version, whereas the original was a text based game; but the game logic has come across cleanly.
The game requires you to make multiple 2x2 blocks (on a 7x7 board), while also trying to stop the computer from making its own blocks.
If someone wanted a challenge, the computer decision making could certainly be improved.
cheers
S.