More Random Observations of Insignificant Phenomena
If a sheet of 8.5x11 in. paper is taped to a wall via the top two corners, over time the bottom half of the page tends to curl inward. The cause of this is unclear but it may be caused by some form of creep or the stresses involved in temperature fluctuation if the top half of the paper is held fixed. Moisture might have something to do with. The curl might act as a sort of temperature gauge that increases curl with heat and the temperature the paper was taped at. The curl might also be used as a way of moving and sorting papers such as those used in copiers and printers.
Gum tends to accumulate on concrete sidewalks over time. The gum is always blackened and flat and proportional to the age of the fresh pavement. The amount of gum covering could be used as a measurement of age or cultural customs. Perhaps it could also be used as a measurement of economic prosperity, littering laws and the perception of littering laws. The gum itself might be harvestable for some recyclable purpose such as adhesives, mortar, or ceramic products.
In most modern toasters, bread crumbs tend to accumulate at the bottom over time. People rarely empty or clean these toasters out during the lifetime of the toaster. The breadcrumbs are usually burnt or dried out and thus do not decompose very well. Any decomposition is usually killed by the daily toasting temperatures that exceed the boiling point of water. The bottom of toasters might serve as an useful testbed for equipment to be used in space due to the extreme variations in temperature and the biological barreness. The bread crumbs might also be harvested and used a source of food or perhaps the base in some recipe.