If sashimi and maki are subjects you take very seriously, check out this over-the-top chopstick holster from Brandon, the incredibly talented 17-year-old behind Vanguard Armament. It ensures your personal set of chopsticks is always close at hand for those quick draw dining situations.
The holster is made from Kydex, a thermoplastic acrylic material that can be moulded when warm, but hardens to a tough durable plastic that's often used to hold knives and guns. But in this case it's used to store a far less dangerous set of tools. At least 'less dangerous' as long as you're not a dragon boat full of raw fish.