This is such a great idea! I wish I knew, I would have donated.

After months of frustration, Ms. Shriver has found someone who will ship her Silly String to Iraq, where troops use it to detect trip wires on bombs. They spray it 10 to 12 feet out and see if the string lands on the ground or hangs on the wires.
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After an initial shipment went to Iraq in January without a hitch, Ms. Shriver – whose son Todd is a soldier there – struggled to find a way to send thousands of cans she was still collecting. One problem was that Silly String, sold in aerosol cans, is considered a hazardous material, meaning that only certain companies can ship it.