(Image credit: Apartment Therapy )
Q Knot Reusable Zip Ties
$6.00 for 12 

A self-locking, non-slip grip, and stretchable design makes these reusable zip ties an easy home office organization tool for handling cable, cord, and stationery storage duties. Throw a couple in the laptop bag, keep the rest around the desk for times when you need to get a wrap on USB cables, headphone cords, and even a collection of pens. Available in a pack of 12, with 4 of each size/color: 4.5″ (yellow), 6″ (green), and 7.25″ (red).