Motion Sensor + Screen Saver = Battery Level Meter

The N702is 3G phone by NTT DoCoMo in Japan has a built in motion sensor and when the screen saver is activated, the screen acts exactly like a glass of water. The "water" level moves when you move the phone around with the information it gets from the motion sensors. The water level reflects your battery status, the lower it gets, the less power you have and therefore needs some juice.