One of my favorite repeat projects are these small boxes and trays that I do.
There really is nothing to them. I cut all of my reclaimed boards to size on my chop saw.
Once I have my boards cut I butt join the corners and attach the bottom with glue and a brad nailer.
This is a simple and profitable project. People love them and are willing to pay anywhere from $10 to $25 depending on size. If you don't want to make your own you can buy one from me here ant my Etsy.com shop.