Ok so 4 gig Nano. Take two of them and you have 8 gig of music. Great for a long trip. So, in order to make this seemless iTunes needs to recognise a logical to phsyical ipod mapping. Take two nano's connect them into itunes. Today it will see them as two separate ipods. That needs to change so that you can create one logical ipod that spans two physical ipods. Alternatively and less sophisticated is to have two separate playlists for each ipod. What you want to void is using one cable for two ipods since you'll overuse the connector.