cheap on ebay
I bought two of the clear ones on ebay for around 15bucks including shipping. With the clear, you can paint using ordinary spray paint on the inside. Just make sure that it is dry before you put the computer in it or it will stick to the computer. I painted one pink for my wife and one black for myself; I even went so far to tape off an inverted apple so that the light would shine through. Pretty cool, huh?
Why I removed these cases?
They clicked when you would move the computer and they added a lot of weight and thickness to the computer. It was too heavy for the hinges, so it made the screen close faster than it should have.
I thought the plastic would insulate my legs a little more, but it seemed to have the opposite effect as it felt hotter. Maybe the computer couldnt cool as well because of the case. I even bumped up the fan control, but that didnt seem to help. I cant quote any actual temperature readings as it was just my general perception.
Really, with the added weight and thickness, these cases made it feel a lot like a dell. If you really want them, I would check out ebay as they are way cheaper than the $50 msrp.
mike