Ask Slashdot: Best computer for a 7-year old child?

Boldizar writes: "My son turns seven next month and I’d like to buy him a cheap computer. I’m looking for the /. hivemind opinion on what would be the best computer for a child. I’m looking for a computer that will teach him basic computer literacy, and hopefully one wherein the guts are a bit exposed so that he can learn how a computer works rather than just treating it like a magic object (i.e., iPad) – but that would still keep him interested and without leaving him behind in school. For the same reason, I prefer a real keyboard so he can learn to type. I don’t know enough about computers to frame the question intelligently. Perhaps something in the $300 range that would be the computer equivalent of an old mechanical car engine. Another way to think about it: I’m looking for the computer equivalent of teaching my son how to survive in the forest should the zombie apocalypse ever come.”"