If you have relatively modern, working electronics and you want to get them into the hands of people who can use them, start with the Cristina Foundation, which matches donors of used computers and other electronic hardware to select a local charity or school in their area of the country. Another organization to consider is the World Computer Exchange, which sells low-cost refurbished desktop computers and peripherals available to developing countries.
There's also a crop of charities seeking to pass along mobile phones to people who desperately need them--groups such as the National Coalition Against Domestic Violence, HopeLine, Cellphones for Soldiers, Operation Gratitude, Hope Phones, Secure the Call, and the 911 Cell Phone Bank.
And keep in mind that if you're giving to a registered nonprofit organization, you may get some tax benefits from your donation (you'll need a receipt with the company's Tax ID on it).
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