Get an Aquapipe (thats the brand name). Its like 4 inches long and the mouthpiece folds so its compact. It was my favorite little device until I lost it. And no one ever knew what it was. My mom walked into my room one day and saw it sitting on my table and she asked me what it was and I told her it was a comp duster. Its very concealable and the hits are really smooth. I got it at my local headshop, but you can probably buy it online or at any headshop near you.