5min 38sec clip - how to #etch #metal using a 9 volt battery.

 

found via a cooltools email

text from youtube "Leah of Seejanedrill shares a surprising metalworking HACK. Leah demonstrates and explains how to etching metal using a 9 volt battery.

Supply List: 9 volt battery or a battery charger white vinegar table salt a resist such as vinyl letters, vinyl stencil, sheet vinyl, fingernail polish etc. alligator clips "

1min 42sec clip - Google Maps Hacks by Simon Weckert

Found via digg, text from youtube "99 smartphones are transported in a handcart to generate virtual traffic jam in Google Maps.Through this activity, it is possible to turn a green street red which has an impact in the physical world by navigating cars on another route to avoid being stuck in traffic. "