thats funny and true, but rags dont functionally replace a couch... but a reused food can does fully replace the function of an ashtray. the rags have no structure, and will be very bad for ur body/postuds unless u use them as building material, for a actual unit of furniture thia might not be a terrible idea as most commercial furniture is all synthetics and glues and various chemicalz which will off gas in your living space. a couch made from old cotton rags and wood, wouldnt contain all those chems. A fire retardant might be worth the health implications tho.

ashtrays are usually what ppl make in crafts when they dont know how to make anything else... ashtrays/bowls/vases