Expertbattery via eBay offers a 10,400mAh Power Bank Battery Pack in Black for $15.50 with free shipping. That's $4 under our January mention and $17 below the lowest total price we could find for a similar battery pack elsewhere. It features 1A and 2A dual USB output and a built-in microUSB cable. It works with iPod, iPhone, smartphones, digital cameras, and other devices.
If the price of ice cream plunges, more people will buy it, right? Not so fast. Watch this video to learn how the human mind influences buying behaviors.