16. Slip-on Solid Shelf Dividers ($7 for two, containerstore.com) keep stacks of shirts and sweaters tidy and can be repositioned.
17. Hang a steel Commercial Grade Extra Closet Rod by Richards Homewares ($17.50, organize.com) from an existing closet rod and double your space, then arrange clothes by use or season.
18. The Battery Rack organizer ($20, containerstore.com) holds everything from AAAs to nine-volts and comes with a tester, so you’ll know which ones are fading fast. Tuck it in a kitchen drawer or mount it to a wall.