Depends on the concept I'm trying to learn. My "go to" for anything UI related is Connect 4. Other than that I try to pick a game that fits the theme. Games

Depends on the concept I'm trying to learn. My "go to" for anything UI related is Connect 4. Other than that I try to pick a game that fits the theme. Games are amazing because they have well defined business requirements with sufficient depth to really exercise your critical thinking skills.