I have three of these that I use for storage at home and also to take to retreats and sometimes workshops. I bought them at The Container Store. You can take units from one and add to another to make even more stacked units. It's on wheels and has a handle for easy transport and movement. They sell for $41.99. It's called The Busy Box "More versatile than your average toy box, this heavy-duty box has wheels for easy mobility. It features three individual stacking boxes for separating and sorting toys (fabric and notions for me). A large handle makes it easy to roll this box from room to room.
I can never successfully upload any picture to this page, so you'll just have to go see it for yourself.
http://www.containerstore.com/shop?p...47&N=&Ntt=busy