If you carry electronics in your bag, you probably have cables, connectors, and chargers in there, too. If the bottom of your bag looks like a nest of snakes, you could benefit from the Cable Wrap from STM Bags. The wrap is made of water-resistant black canvas, and it rolls up into a 10.2″ X 5.9″ X 1.3″ package. Inside are various sizes of pockets and a zipper pouch to organize headphones, cables, pens, and chargers. STM has a dealer location option on the Cable Wrap page, or you can purchase it from Adorama in the US for $25.