Amazon offers its Amazon Prime members the Sennheiser HD 408 Headphones for $24.99 with free shipping. (Non-members can spend $25 or more to qualify for free shipping; otherwise, shipping adds $5.58.) That's $15 off and the lowest total price we could find. These feature an open-air design and flexible headband.

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