Do you have one of those laptop cases that unzips all the way to lay flat, and is lined with a flannel-like material. Those are great for organizing your craft supplies for an on-the-go project case.
I had a case from a Sony Vaio like that, and when the computer was "gone" (kaput, doorstop fodder, extinct - you get the idea), I turned it into a bead project case. I took the leftover containers from my son's Gerber baby food (the new plastic ones with snap on lids) and put heavy duty adhesive velcro on the bottom (the hook side). These stick to the flannel lining of the case, and I can hold 15. The outside pocket holds my pliers and other tools that don't fit in the containers. When I need to go teach a class, I just zip up my case, and I am off. It even has a handy dandy shoulder strap.
If you don't have the lined case to use, you can just use both sides of the velcro and stick it to whatever case you want to use (or make your own case-for those so inclined to do that) - it just makes it a little pickier for positioning your containers, so you probably want to pick the containers out before deciding where your velcro should go.
Sorry - no pictures - if I keep writing these I really need to get on the ball and get some illustrations going. At least I managed 2 weeks in a row, so I am on a roll, right???