Today only, All4Cellular offers the Stitchway 1900mAh Backup Battery for iPod / iPhone, model no. CHEX-ALL-BK-08-319, for $3.95. Coupon code "A4C1A1" drops it to $3.75. With $2 for shipping, that's 24 cents under yesterday's expired mention and the lowest total price we've ever seen for this battery. (It's also a current price low by $2.) It purports a full charge in less than two hours. Coupon expires January 11.