Umm, the best case ever is probably made by this Japanese company called Arvel. Now there website is Japanese only, but I brought my case of of some guy on Ebay. Now I believe the correct model number/size for a 12" iBook like mine is the NSB5. Now they make them in 3 different colours, BK for grey, BL for blue and GY for white. You definantly wont want the Blue for an iBook. Get either a grey or white one. I brought a grey one because I wasn't sure if I was going to get an iBook or Powerbook, since grey will work for both, plus it doesn't get dirty. If I was sure on getting an iBook, you might want to get the white one since it will match it perfectly if you don't mid it getting dirty.It is very protective, the outside is hard plastic. The inside is that memory foam stuff so your laptop stays firmly inside without sliding around when you are carrying it. The beauty of this case is it feels like a binder, and fits perfectly in your backpack like it was a binder. Very compact around the laptop, adds very minimal size for the protection. It's just like carrying a book around with you and once the case is ziped up, you feel perfectly safe of the book inside. Also, unlike other cases, you can use the laptop while still in the case. That way you dont have to put your laptop on possibly greasy cafeteria tables at school and the bottom of your laptop will not get scratched up. So ya, for a 12" iBook get the NSB5BK if you want grey or the NSB5GY if you want white.
This is their website, you'll have to scroll down to get the right model numbers:
http://www.arvel.co.jp/htmls/cover/bag.html
Edit: I dug through my records to about a year ago and the guy I brought it from his eBay user ID is tenikiti from Japan with very good feedback. Search for him on eBay. His current items for sale don't include these hard models, just some softer more uglier ones and he did not have it for sale either when I brought mines. If you want one of these cases send him a message, and he'll go and buy you one I guess and list it on eBay for you to buy. This is the only way to get these cases aside from going to Japan because they are not sold anywhere on the net that ships outside Japan as far as I'm concerned, and unlike those Bitolithic pouches, will actually protect your laptop in a drop. Plus their hard cover design makes them very fast and east to unzip since the softer cases you sort of have to hold the material while you're pulling the zipper.
P.S. Now that I know I'm buying a new iBook and not a Powerbook, I wish I got the white case since that was obviosly specificlly made to match the iBook. That white case will look HOT with an iBook, I might end up purchasing a white one from the guy and giving the grey one to my friend so he can use it for his 13.3" Sony VAIO S-Series laptop. And by the way, the NSB5 size fits standard 12.1" and widescreen 13.3" laptops. So you can buy this now even if you're worried if Apple changes the form factor to widescreen 13.3" like the rumors say. It will fit.
