I built an apple box out of a scrap of 3/4" plywood that was too good to throw away, but I had no good place to store it in my garage. I constantly had to move it out of the way when I wanted to work on any project. It became a consistent source of aggravation. When it transitioned from always being in the way to silently taunting me I knew it was time to bust out the table saw and compound mitre saw.
After cutting the pieces to size, I joined the pieces using glue and biscuits to avoid any visible nail holes. Since then I've built a second one using a piece of plywood from a pallet my brother in law was trying to discard. That one I joined with a combination of pocket screws and glue and biscuits.
Both are of standard apple box dimensions and have a structural rib in the center. I rounded all the edges with a 1/4" router bit, and I made one sound friendly modification. Instead of standard cut outs for the handles, I made one side bone shaped to accommodate two boom poles. This design is quite functional and it is much more comfortable to sit on than your typical apple box. I'm still deciding how to finish the second one.