A lot of shoeboxes can be unfolded to lie flat. This helps a lot in storing the ones you haven't re-purposed yet. When you re-fold it, do it so it is inside out. Then it makes a very good mailing box as you can just write the address on the box then tape it up securely to go through the mail. I also re-fold them inside out to use as storage for craft items like fabric paint etc.
Here's an extra "box" hint. I cut the boxes that bath soap comes in (like Dove or Caress) in half, then fill up the bottom of a shoebox with the half-boxes. Each box will hold two Scribbles bottles upside down. This helps preserve the paint in the bottles for years as any dried paint will be on the other end so it won't affect being able to squeeze it out of the tip. I've used some that are over 5 years old!
By DeBushe from San Jose, CA
From storage to crafts, shoeboxes can used for all sorts of things. If you can get them for free, even better! This is a page about getting free shoe boxes.