Spinning mobile phone battery

I found this one over at the superb Yanko Design blog and it caught my attention straight away.

The concept is simple; a mobile phone battery with a finger sized hole in it. This allows you to spin the darn thing around and around really quickly and really easily. That’s a chance to pump some juice back into it. Hide the hole under two covers and most phones won’t have a problem with the design.

I imagine, though, as phones get smaller then this design might have some challenges ahead but for now the concept pretty slick!