I’m filing this under “cool shit I didn’t know about”. It turns out that if you cut a standard 9V Duracell you will get 6 small 1.5V battery cells which are essentially your standard AAAA batteries:
images © axecollector.com
Interesting. I had no clue that this was how they made them.
[tags]9v, batteries, aaaa, 9 volt, 1.5v, 1.5 volt, duracell[/tags]