Fly Tyer Tubes
I first came across these fly tyer's tubes in Kelly Galloup's The Slide Inn video series on Youtube, and have been using them travelling with flash, thread spools, and anything that will fit really (even feathers at times). I think they are pretty handy, and I think you'll find quite a few uses for these too. 

Each tube is 12" long with a 2" opening. This size holds 6-8 bundles of flashabou without much cramping, but I've help up to 18 bundles while travelling. It also holds  or 15 spools of thread easily *stacked on side, not top*, so is perfect to help organize your bench or to use when traveling.