Only carrying necessary stuff when travelling has to be a good way of cutting carbon emissions. I wonder if there's some room for more innovation here?
For example, if you're travelling long-haul, I wonder if it makes more sense to leave your toothbrush behind and buy one at the destination? I wonder if airports will start seeing a ramp up in the trade of loaning / purchasing material things. The idea being the only thing you need to send half way around the world would be your body (and some garments for modesty ;-)).