What a fantastic question. Its early so my brain isn't on total function yet.
Recipe box Large size to hold computer program CD's
mole foam--cut a small strip and stick to your machine bed for a seam guide. Just measure your exact 1/4" and lay the mole foam down.
Mole foam square on front of machine to hold pins as I take them out of a project.
Pizza boxes (I buy them from the pizza place) for storing blocks in progress
Plastic knife to close pins when basting a quilt
Ziplock bags to transport projects to work on in waiting rooms etc.
Thats all I can think of right now. Thanks everyone for sharing their "other use" hints.