I always travel with only one carry on bag and mostly on business. I _always_ buy a fridge magnet wherever I go for the first time, mainly because its easy to carry back but also that its a cute reminder of places I've been to. My goal is to eventually get a world map that is magnetized, put it up on the wall and place my magnets on them. I have no idea where to put it, even if I find this map, because it would likely have to be big enough to accommodate several magnets. Right now, I've stuck them all on one side of my fridge.

Beyond my magnets, I carry a ultra-sil overflow bag inside my carry on - I sometimes pick up other larger stuff (plates, a bottle of whiskey if applicable, etc) from airports but only on my way back home and only if its a direct flight.