uh, even when just commuting to work every day, every gram saved makes a difference. when buying a new laptop, weight is my primary selection criteria, next is size and price, and only then any features. (although features factor into price)

the only time when weight is not a consideration is when getting a machine that i don't intend to move but just keep at home/work. but even then, i get annoyed when i occasionally have to carry around, or decide to change the purpose of the device.