Since 2001, Sprint has recycled more than 48 million phones, which includes at track NASCAR fan cell phone recycling, which in turn equates to more than 2, 600 metric tons of material.

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For users who want to offer their support, the HopeLine app makes it easy for wireless users to donate no-longer-used wireless phones and accessories to HopeLine, Verizon Wireless' national cell phone recycling program.

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Elham Ebizadeh, who runs a cell phone refurbishing and ring-tone business in Los Angeles, added a collection and recycling company last year, handing out 500 drop boxes in grocery stores and other locations.

FORBES: Use It Up, Wear It Out