The Fish Dish is a breakout/add on board for the Raspberry Pi (can be used with other boards too - Arduino etc.) which makes it easy and extremely fun to use the GPIO on the Raspberry Pi. It plugs directly onto the GPIO pins with a 2 x 13 header and is in the shape of a three-eyed fish.
It has 3 LEDs (red, yellow, green), a buzzer and a switch. The Fish Dish can therefore be used to showcase a variety of different interfacing techniques, and brings physical computing to the Raspberry Pi in a cute and cheerful way!
It will also come with a stacking header (as pictured) meaning that you can still use the other GPIO pins if you wish.