Wearable technology has come a long way in the last few years, and one of the top products on the market has been the Fitbit. Right now on eBay you can get the Charge 2 heart rate and fitness wristband for only $109.99 with free shipping. The device is available in black, blue, plum, and teal in sizes small and large. The same item sells for $148.95 on Amazon.