Groupon offers the Mophie Juice Pack Helium 1,500mAh Rechargeable Battery Case for iPhone 5/5s, model no. JPH-IP5-SLV, for $39.99 with free shipping. That's tied with last week's mention and the lowest total price we could find by $10. It features an LED power indicator, forward-ported acoustics, and capability to recharge the phone and case simultaneously. Deal ends November 12.