one of the things i would hate to live without is toilet paper and i always carry a roll when i'm traveling, especially by train. but it's tough to carry in a bag... it unravels, the layer of paper on the outside doesn't stay quite clean and you end up wasting a lot, it gets all squashed and mis-shaped, and it's not the right size to be held in one hand or kept in the pocket while maneuvering indian train bathrooms. on the long train ride to bhopal i thought of this design for a traveling toilet paper dispenser that might fix all those problems. here, the toilet paper is inside the cardboard tube instead of around it, with a small perforation or flap for dispensing.
also a good way to recycle all those cardboard tubes that just get thrown away.