I have been making a few zippered pouches with boxy bottoms and they turn out so wonderfully every time! So cute! I used strips of scraps for the one shown below, even some selvedge! The selvedge is the self-finished edge of the fabric and usually has the designer/company's name and dots of the different colors used in the fabric.
The pouches all have a layer of fleece and a layer of stabilizer, making them very sturdy. I have 5-inch and 7-inch zippers available. Scrappy Strips Zippered Pouch (like the photo) $15, Regular Zippered Pouch $11.