It is no secret that you can create all kinds of fun gadgets with Arduino. The Arduboy is well worth a look. It is a credit card sized game system, powered by Arduino, that lets you play games anywhere. It has an OLED display, 6 buttons, a speaker, and 8 hours of battery life. The Arduboy has an aluminum and polycarbonate construction.
The fun part is anyone can make games for the Arduboy. You can also use this to teach kids how to program. Arduboy can be programmed using the Arduino IDE. The device has a 180 mAh battery inside. It is compact enough to fit in your pocket easily.