One Laptop Per Child
The One Laptop Per Child program has the mission of bringing, you guessed it, one laptop to every child in the developing world. They haven’t reached their stated goal of a $100 laptop, but $200 still isn’t bad, and the laptops have entered “mass production” mode. You could buy one with the refund from your iPhone.
Starting November 12, they’ll be kicking off the “Give one get one” program - for $400, you can donate a laptop to a child in a developing country and get one for yourself to give to a child of your choice (or just keep, I suppose).