PricePlunge offers the Powerocks Magicstick 2,800mAh Universal Extended Battery in Orange, model no. 370854, for $3.99. Coupon code "coldplunge5" cuts it to $3.79. With $2.99 for shipping, that's the lowest total price we could find by $2, although we saw it for a buck less last week. It features an LED charge indicator and microUSB charging cable. Deal ends March 31.