Low cost alternatives to organize

You don't always have to have a lot of money to organize. You can use your imagination to help solve some problems.
This is an example of storage for some house blueprints that a client needed some storage for.
We simply took several narrow boxes that we were going to throw out and stacked them on top of each other to make some of his plans close at hand (but still achieve storage). I have to admit, although I would love to take credit for this solution...it was his wife who saw the boxes and figured it out. I think I would have been too concerned to offer boxes to many clients as a solution before that, but I realize that we all want low cost alternatives and worse they could say (other than "You cheap-o..I want another organizer!") would be, "No, that doesn't work for me".
This is what we came up with for his office for the plans he was currently working on.
I had researched all kinds of products for him and there are many out there, both for long term and short term, but he was trying to keep expenses down. In his office he did opt for some storage cubbies that were a low cost alternative to the expensive drawer options that we looked at. He wanted some of his plans to lay flat, others rolled. It bothered me that they were sticking out, but he was alright with that and out of the options, this is what worked best for him, and what he chose.
There can be many low cost solutions that you can find for organizing, you do not always have to run to the store for everything. Here are just a few examples:

egg cartons - take the top off and use in desk drawer for paperclips, rubber bands..
candy trays (inside candy box) - jewelry, earrings, desk drawers..
check book box - inside "junk drawer" to organize little thing ...
inside grid from a fruit (pears, apples) box - great sock organizer for drawer
Many many more....

What are some other ideas that you have used or can think of?