Donor Bikes. I ride several mid 80's sport touring style bikes as commuters. To keep them maintained and accessorized, I buy unwanted ladies road bikes (usually less the $10) at garage sales. I can then salvage bike bags, bottle cages, aluminum rims, tires on ocasion (but almost always the tubes), rear racks, fenders, pumps - handlebars, shift components and an occasional chain. It takes some effort but as you say I enjoy a challenge.