I've been using this same style box for about 15 years to organize my entire life in. I use them for projects, crafts, household odds and ends and the size is just PERFECT. They stack nicely, they're cheap, durable, and the clear plastic makes them easy to see whats inside if I didn't get around to labeling them yet. 

Please don't discontinue them! They seem to be getting harder and harder to find and I'm afraid one day I'll need to organize more stuff and I won't have stack-compatible boxes to do it in anymore! :P