You always see night lights in warm whites, but if you're up for something colored, you can try these LED Concepts Plug-In LED Night Lights. The green and blue-colored night lights are ultra slim and do the same job of lighting up your area at night.
They automatically turn on when your daylight bulbs are turned off or when they sense natural darkness. Since they're made from LED lights, you can expect a pretty long lifespan. They're practically low maintenance with no need of battery replacement or light bulb replacement.