newegg offers the Tekkeon 4,800mAh Pocket-Sized Rechargeable Battery Pack in Black, model no. MP1820, for $29.99. Coupon code "CLRNCMDNS31" cuts it to $24.99. With free shipping, that's the lowest total price we could find by $5. It features one USB port, USB cable with micro USB and mini USB adapter tips, and more. Deal ends April 1.