I heard about One Laptop Per Child (OLPC) last week and it's doing good in quite an interesting tech-saavy way. This organisation aims to have one laptop per child:

To create educational opportunities for the world's poorest children by providing each child with a rugged, low-cost, low-power, connected laptop with content and software designed for collaborative, joyful, self-empowered learning.

People can help out by paying for a laptop, being a translator, providing tech support to kids/adults, or even helping to develop software (games, tools, programs)! Very cool : )
It also seems that people can help by testing the laptops to make sure they run ok before they're given away (someone had mentioned it to us). There's workshops in Wellington doing this, so it must be quite widespread round the world?