I'd like to get a few examples going, if possible, of people's homemade pet toys.
If it's true for your pet, as it is for my cat, that bits of packaging can elicit more excitement than any full-priced toy, please show me your free/cheap 'n' cheerful makeshift pet toys.
My cat loves feathers. Especially if it's a really good flyer. I stand on the stairs and float them down to her to catch. She also enjoys jumping about in tissue paper, so I save it up and stick it in a box for her. By poking small holes in the box, I can push a stick through and make the tissue paper move - she goes wild for that.
I remember keeping loo roll cardboard tubes for my hamster when I was a kid too.

Now how about yours?