A4C offers this Apple 30-Pin Charge and Sync USB Data Cable for iPhone/iPod in White, model no. MA591G/B, for $3.95 with free shipping. That's tied with our October mention, and aside from the mention below, the lowest total price we could find for an Apple-branded cable by $3. Deal ends May 19.
A close price: ChargerBuy via Rakuten offers this cable for $4.19 with free shipping.