Katy Perry recently took to the red carpet wearing a shimmering gown studded with thousands of blinking rainbow lights, and we were impressed by this LED-laden coat that keeps bicyclists safe when they hit the streets at night.

ENGADGET: Inhabitat's Week in Green: salad spinners, diapers, and solutions to the Deepwater catastrophe

Red is the colour of love and that will be the colour of the lights radiating from the historic building on St Valentine's Day, while rainbow colours will mark Belfast Pride in July.

BBC: Rays of light over Belfast City Hall