Netbook Bag
There are many types of bags and cases for netbooks and since needs and requirements of everyone are different, you will want to choose that particular case that suits your requirements. Here are some major types

Netbook Travel Bag – If you travel a lot with a lot of netbook accessories, we recommend getting one of these. They are much bigger than a case or a typical bag, but they let you carry every single accessory you use with your netbook. [link for above mentioned case]
– link
Netbook Case – It is type of brief case that has a handle and is made from faux leather. The netbook case usually has plenty of pockets which is important for a netbook as you have to carry cables, SD cards and so before you move out of the house.
Pouch – It is a bag without any straps and is great if just wish to have a simple covering for your netbook. They hold the netbook really tight and we recommend them only for netbooks with 10.1 inches or smaller displays. Recommended ones include the one from Case Crown – link

Netbook Skin – If the only thing you plan to carry is the netbook and nothing else, consider getting a skin. While it does not provides protection against bumps, it does provides ample protection from getting your netbook scratched. They are cheap too.
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