https://www.codingame.com
Learn to code by solving game situations
https://www.codeeval.com/
More traditional programming challenges gamified
https://codecombat.com/play
Learn Python/Javascript with a game
http://www.jsdares.com/
Navigate robot with simple programming
https://scratch.mit.edu/
Visual programming, interactive presentation creation and remixing other ideas
https://screeps.com/
MMO strategy for programmers (thx Laurent!)
https://vim-adventures.com/
Learn VIM by playing a game 🙂