HandHeldItems.com offers the HHI Apocket 1750mAh External Backup Battery for Apple iPhone 3G / 3GS for $24.99. Add coupon code "hhiapocket1750" to your cart to cut it to $19.99. With shipping at $5.95, it ties last week's mention as the lowest total price we've seen for this type of iPhone backup battery. It features a slim protective case, dock connector port, built-in LED flashlight, and more.