From an anonymous communique:
"Tried out our new extremely corrosive ammonium bifloride/sulfuric acid bomb on a McDonalds in Utah.
Ammonium Bifloride is corrosive when applied to glass. It is easy to come by via internet or craft store. Sulfuric acid is water soluble and corrosive as well.
You can put the mixture in glass bottles and throw it at windows. If the window doesn't break then the contents inside will be sure to make the window unusable.
Other uses: put in glass spray bottles and simply spray 'paint' windows which will then become ruined completely.
The options are endless. If you are not comfortable with making your own. They sell glass etching solutions ready to go on the internet and in craft store. A lot of these are like paint and meant to stencil designs on windows. When the windows are sprayed with water, the chemicals react and they corrode the glass. So make your own stencils. When they come to clean off the 'graffiti' with water they will actually be doing your work for you.
We have a lot of this stuff. The window replacement companies are going to be really happy this year.
Chemists for Animals"