Cheap AAA batteries extracted from 9V batts

Duracell's 9-volt batteries contain six 1.5 volt batteries that are each nearly the same size as a AAA battery, close enough that you can substitute them. The gimmick is that a 9V battery costs lots less than six AAAs -- which means you can save a fortune on finicky little batteries by performing minor surgery on 9V batteries. Link (via Gizmodo)