In preparation for the 4th of July, NPR had a special Science Friday segment on homemade fireworks. Some of the highlights:

• A guy on the northern border called in to say that his 4th of July tradition is to shoot fireworks at Canada.
• Steel wool is not only flammable but makes a great display when ignited by a 9-volt battery and swung around on an unfolded wire hanger.
• Host Ira Flatow loves hitting a whole set of caps with a hammer.

What a great country.