The MSI Wind U120 is a great second computer to take to the coffee shop, on airplanes, to the library, or even to the park.  After having this computer for four months, I consistently get 4-5 hours from the battery depending on what programs I am using.  It comes with its own case and is about the size of a Bible - I can even fit it in my purse.  It also has the advantage of a "real" hard drive with Windows XP, while most other similarly-priced netbooks have the kind of memory & OS you would find on a smartphone.  I also find the keyboard more workable than the other small netbooks I tried....