TechRabbit offers the refurbished Mophie 4,000mAh Juice Pack Powerstation Portable Battery Pack in several colors (Purple pictured) for $9.99 with free shipping. That's $4 under the lowest price we could find for a new one. This external battery works with USB-based mobile devices and smartphones. Deal ends April 2.

Note: A 1-year TechRabbit warranty applies.