By recycling mouse pads into shoe insoles you get a much more comfortable insole than is usually available in stores.
The durable foam material in mouse pads make them a great free source for making your own boot insoles. Recycling mouse pads for shoe insoles is easy. Simply trace around each foot while standing on a pad, then allow for a bit more material all around. Trim to fit with scissors.
My relatively small Size 8s mean two pads are generally just right. Larger-footed folks will probably need a third pad in order to have enough material to piece together.