Seat from a bicycle would make a nifty little stool.
Tire tread as replacement sole for boots.
Wire saw using the brake cable. Probably lousy for cutting branches but might work as a vertical saw attachment for the pole lathe.
being low on funds and/or having only limited access to raw materials means i'm a bit of a "pack rat" and have gotten rather adapted at repurposing over the years.... recent example: a while ago i saw a piece of handle poking up on the beach which turned out to be a machete sticking out of a banana "log" (my guess it got forgotten in the banana which then got washed downriver in a flood and then spent some time floating in the ocean before being washed ashore).as there was a big chunk missing near the tip i reshaped it with a grinder, made a scabbard out of a scrap piece of pvc pipe over the fire and sewed a belt loop from some webbing -- now it's my "beach machete" (blade length ca. 13" ), it's compact size makes it ideal for taking it with me on the bus when visiting friends, too (wrapped into a shirt and carried on my backpack; as everyone here uses machetes == no problem )