Bought a cheap EVA netbook slip cover.
You probably don't want something that's always on the thing because it's so heavy already for when you are reading with it.
I just threw a piece of foam inside of it so that it fits well if I have to move it or throw it in a backpack, and it's well insulated:
http://www.amazon.com/CaseCrown-Line.../dp/B003EVVAFQ
If you want something that fits a little better but is less durable, but still cheap, i'd go with (just ordered this now, looked good, got the one with
map pattern):
http://www.amazon.com/gp/product/B002NJGLEK
CC cases are cheap but pretty decent quality. The seams are nice and the materials are good. They feel sturdy and don't fall apart.