Let Me Out" is a board game with the goal to move the magenta block, the biggest one, from the middle of the top to the middle of the bottom. You need to move other blocks and make room for the big guy. The game has 3 levels, beginner, intermediate, and expert. You can change the levels from the menu.
The amazing thing about this software is that it only has 2 main classes, Block and Board. And the code is very simple. So, I think it is good for beginners to learn Object-Oriented programming. Or, hopefully fall in love with gamedeveloping. :) Another interesting thing about it is the UI design. I saw a lot of board games in which the user needs to either drag-and-drop or use several steps to move an item. That's because to let an item move, the user needs to tell it to move and where to move. This game uses an arrow to show the direction that a block will be moved, which changes with the mouse movement. Since the user already has the direction, all she/he needs to do is just one click.
Before you continue reading, I suggest that you play the game and have fun. You may want to change the level to Beginner to get familiar with the user interface.