Although this is only available for N702is 3G phones in Japan on NTT DoCoMo, it was too cool to not show you guys. The phone ship with a screen saver that, when activated, looks like the inside of a glass of water. The 702 has a built-in motion sensor, so as you tilt it, the water level changes to match the orientation of your phone. Not only that, the amount of water it has reflects how much battery power you have left! Is that not awesome, or is that not awesome?
An Interesting Way of Showing Battery Status [Slashphone]