Amazon offers its Prime members the Thermos 16-oz. Stainless Steel Food Jar in Teal for $20.29 with free shipping. (Non-members can get free shipping with orders of $25 or more; otherwise shipping adds $5.58.) That's an overnight price drop of $7 and the lowest total price we could find by $5. This vacuum sealed jar can keep food hot for up to seven hours, or cold for up to nine hours.

Amazon Prime membership is $79 per year; however, Prime is free for college students for six months, and free for parents and caregivers for three months.