A Reusable Mug: Stojo 16-Ounce Biggie Collapsible Cup This Stojo 16-Ounce Biggie Collapsible Cup ($20) is smart, because they can easily pack it in their bag. It can go anywhere with them. Image Source: madewell.com Stojo 16-Ounce Biggie Collapsible Cup $20 from madewell.com Buy Now