well rats are wonderfull companions, they are very chep to travel with an inexpensive when it comes to food, rats will eat just about anything so when i ate my rat would eat with me i would never have to buy food for him. i bough one bag of food put it in my pack for emergencies but hardly had to feed him. If you raise them from babies and train them to stay on your shoulders they will just sleep on you, they are also like portable toothbrushes, cause they like to eat the plaque of your teeth, they are allaround the best companions to travel with.