One of the things I dislike most about notebooks and especially netbooks is the track pad. Most netbooks have the track pad so close to the keyboard that I end up hitting the track pad with the palm of my hand while typing.
That means I like to have a notebook mouse with me at all times. One of the coolest mice for notebooks is the Mogo Mouse that stores in the PC Card slot. The catch for netbooks is that the little machines lack a PC Card slot.