Adafruit 2864, NeoPixel 40 RGBW Warm White LED Matrix Shield for Arduino [2864]; 124-5493

Complete with 40 ultra bright LEDs in an 5 x 8 layout, this Adafruit NeoPixel Shield is a truly brilliant lighting solution. Each NeoPixel is 'split' - one half RGB, the other a white LED - and this combined LED lets you select any colour or illuminate using with white light. It's available in three tones – warm white (3000K), neutral white (4500K) and warm white (6000K). For the finishing touch, you'll find this LED matrix shield slots neatly on top of you Arduino board.